Effects of core strength training using stable versus unstable surfaces on physical fitness in adolescents: a randomized controlled trial

Effectiveness of 12-Week Core Stability Training on Postural Balance in Soccer Players With Groin Pain: A Single-Blind Randomized Controlled Pilot Study

BACKGROUND

Core stability training (CST) is effective in improving postural balance, core endurance, and self-reported outcomes in different populations. This study aimed to investigate the effect of CST in soccer players with groin pain (GP).

HYPOTHESIS

CST would improve postural balance performance, core endurance, and self-reported outcomes in soccer players with GP.

STUDY DESIGN

Randomized controlled trial.

LEVEL OF EVIDENCE

Level 2.

METHODS

Soccer players with GP who met the selection criteria were assigned randomly to a CST (CSTG, n = 10) or a control (CG, n = 10) group. The CG undertook no additional physical activity program besides their usual training. The CSTG performed a 12-week CST comprising 76 ~75 min sessions. Static (force platform) and dynamic (Y-Balance test) postural balance, core endurance (McGill trunk endurance tests), and self-reported outcomes (Copenhagen Hip and Groin Outcome Score [HAGOS]) were assessed before and immediately after the 12-week CST.

RESULTS

Significant improvements were seen in dynamic postural balance (P = 0.04 to <0.01), HAGOS scores (P = 0.02 to <0.01), and core endurance measures (P < 0.01) in the CSTG in posttest compared with pretest session and compared with CG. Static bipedal postural balance measures showed significant improvements (eyes open, P = 0.02; eyes closed, P < 0.01) in the CSTG in posttest compared with pretest session. However, no significant differences (P > 0.05) were observed between CSTG and CG after the training period.

CONCLUSION

A 12-week CST improved static (foam surface) and dynamic postural balance, core endurance measures, and HAGOS scores.

CLINICAL RELEVANCE

The beneficial effect of CST on improving postural balance, core endurance, and self-reported outcomes in soccer players with GP suggests that this training would be an important feature of rehabilitation programs for these players. Coaches and clinicians should prioritize CST training when designing rehabilitation programs.

Effects of an integrative warm-up method on the range of motion, core stability, and quality of squat performance of young adults

Introduction

This research aims to determine the effects of an integrative warm-up method on the range of motion in joints of the lower extremities, the strength of the stabilizer trunk muscles, and the quality of the basic movement patterns in older adolescents.

Methods

The study sample consisted of 88 male students (age 20.1 ± 0.5). They were randomly divided into four groups: one control group (CG) (n = 17; 180.8 ± 7.9 cm; 82.3 ± 8.3 kg) and three experimental groups (EG): EG1 (n = 23; 180.9 ± 7.0 cm; 78.5 ± 9.5 kg), EG2 (n = 31; 182.2 cm ± 7.3 cm; 79.5 ± 11.5 kg), and EG3 (n = 17; 183.3 ± 4.9 cm; 77.5 ± 11.8 kg). The participants were subjected to a 6-week experimental treatment: EG1 once, EG2 twice, and EG3 three times a week. The experimental treatment consisted of four sub-phases representing the integrative warm-up Method: 1) Inhibition (self-myofascial release using a foam roller); 2) Lengthening (Static stretching in a maximum range of motion position); 3) Activation (Positional isometrics muscle activation of the trunk and gluteus); 4) Integration (Integrated all the previous phases into one complex movement pattern). Based on the covariance analysis (ANCOVA), statistically significant treatment effects were observed and positive changes were determined in all experimental groups.

Results

The differences between groups were observed in the following variables: Overhead Squat Assessment (p = 0.000; η p 2 = 0.318 ), range of motion of left hip flexion (p = 0.000; η p 2 = 0.371 ), range of motion of right hip flexion (p = 0.000; η p 2 = 0.051 ) and range of motion of right hip extension (p = 0.051; η p 2 = 0.088 ), Double Leg Lowering Test (F = 2.411; p = 0.014; η p 2 = 0.014 ) and range of combined motion (plantar and dorsiflexion) of left ankle joint (p = 0.000; η p 2 = 0.299 ). There was no significant difference in the Plank Test (F = 1.007; p = 1.007; η p 2 = 0.035 ), range of combined motion (plantar and dorsiflexion) of right ankle joint (p = 0.088; η p 2 = 0.170 ) and range of motion of left hip extension (p = 0.158; η p 2 = 0.060 ). The participants of CG statistically significantly differed from EG1, EG2, and EG3 in the squat performance after the applied treatment.

Discussion

The effect of the treatment was the occurrence of a transformational processes in almost all measured variables. It can be concluded that the integrative method is effective and applicable in practice for both young adults and recreational athletes.

A Quasi-Randomized Clinical Trial to Compare the Effects of Suspension Versus Instability Training on Balance

CONTEXT

Suspension training devices are becoming increasingly popular. Most studies analyzed the effectiveness according to diverse measures in patients with or without conditions at any age. The characteristics of suspension training are very specific and can increase instability and; therefore, enhance balance. The goal was to determine the effects of suspension training on balance by comparing it with instability training.

DESIGN

Two-arm, randomized trial.

METHODS

44 young adults, aged 22.4 years old, with no musculoskeletal condition, took part. There were 2 interventions, suspension and instability training, designed with 12 sessions in 4 weeks. The primary outcome was the Y-Balance test. Other balance outcomes were the Emery and jumping sideways tests, and platform measures while standing.

RESULTS

Suspension and instability training were effective in enhancing balance in terms of the primary outcome, the Y-Balance test, with no between-group differences. Instability training enhanced the Emery test over suspension training (P = .018), but the latter was more effective in the jumping sideways test (P = .003). Neither of the training improved static balance measures.

CONCLUSIONS

Training with suspension devices is effective in enhancing dynamic balance, with similar improvements to instability training. Importantly, the magnitude of change and the frequency of responders to intervention in terms of motor coordination and keeping balance in unstable conditions appear to be sensitive to the type of training.

Responsiveness of monopodal postural stability tests in recreational athletes

Background

Stabilometry, the modified Star Excursion Balance Test (mSEBT) or the Emery balance test (EBT) are reported in the literature to reflect changes after an intervention in monopodal postural stability. Even so, the responsiveness of those tests has not been evaluated after an instability training programme or analysed using multiple statistical indicators of responsiveness. The main aim of this study was to analyse the responsiveness of the stabilometry, mSEBT or EBT.

Methods

Thirty healthy recreational athletes performed a 4-week programme with three weekly sessions of instability training of the dominant lower limb and were evaluated using stabilometry, mSEBT, and EBT tests. Responsiveness was quantified based on internal and external responsiveness.

Results

EBT and all parameters in mSEBT for the dominant lower limb showed large internal responsiveness (SRM > 0.8). Furthermore, mSEBT values for the non-dominant lower limb (except anterior displacement) also experienced significant changes with an associated large internal responsiveness. None of the stabilometry platform parameters showed a significant change after the intervention. The ability of the EBT to discriminate between the dominant and non-dominant lower limb (i.e., trained vs untrained, respectively) was generally acceptable (AUCs = 0.708). However, none of the parameters of the mSEBT test showed an acceptable AUC.

Conclusions

EBT showed a positive responsiveness after instability training compared to mSEBT, which only showed internal responsiveness, or stabilometry platform measures, whose none of the parameters could identify these changes.

The effect of core stability training on the balance ability of young male basketball players

Introduction: This study aimed to investigate the impact of a 10-week Core Stability Training (CST) compared to Traditional Strength Training (TST) on the balance abilities of adolescent male basketball players. Methods: Subjects (age: 15.70 ± 0.75, height: 178.4 ± 8.31, weight: 66.55 ± 8.34) were randomly assigned to either the Core Stability Training group or the Traditional Strength Training group. Three selected balance assessment indicators included the Single-leg Standing with Eyes Closed Test, Star Excursion Balance Test, and Core Four-Direction Endurance Test. Results: 1) The scores were significantly different in both groups before and after the Single-leg Standing with Eyes Closed Test; (p < 0.01, d = 1.692, d = 1.837); 2) In the Star Excursion Balance Test, the scores of the experimental group showed significant difference (p < 0.05) or highly significant difference (p < 0.01) with an average effect size of (d = 1.727) when the left or right foot supported in the other directions before and after the training. However, there was no significant difference in scores in the c direction when the left foot supported (p > 0.05, d = 0.954); 3) In the Core Four-Direction Endurance Test, there were no significant differences in scores for the control group before and after training (p > 0.05, d = 0.567), while the experimental group showed significant differences in scores before and after training (p < 0.05, d = 1.889). Discussion: Both CST and TST were effective in enhancing the balance abilities of adolescent basketball players. CST, in particular, demonstrated improvements in dynamic balance and agility across multiple planes. Basketball coaches are encouraged to consider incorporating CST training programs into their overall training plans for optimal balance enhancement.

Effects of adding high-intensity training during an 8-week period on maximal oxygen uptake in 12-year-old youth athletes

PURPOSE

Maximal oxygen uptake (V̇O2max ) increases during adolescence parallel to the increase in fat-free mass (FFM). How much endurance training adds to this effect is still controversial. Our aim was to investigate if inclusion of high-intensity training (HIT) during an 8-week training period was superior to low-intensity strength and coordination training in 12-year-old youth athletes concerning the effect on V̇O2max .

METHODS

Thirty-five cross-country skiers were randomized into a HIT group (ET) and a strength and coordination group (SC), while 29 less active peers served as controls for growth and maturation (C). Anthropometrics and V̇O2max were assessed before and after the training period, and level of physical activity and training were monitored with accelerometers, training logs and a questionnaire.

RESULTS

The number of weekly training sessions were higher for ET (4.6 ± 1.2) and SC (4.1 ± 1.0) compared with C (1.8 ± 2.0) (p < 0.01), with only ET conducting HIT sessions (1.9 ± 0.2 per week). C spent more time sedentary and less time in moderate and vigorous activity compared with ET (p < 0.05). All groups had a similar %-change pre-post in absolute V̇O2max (mL min-1 ) of 6% ± 6% for ET (p < 0.01), 5% ± 7 for SC (p = 0.14), and 5% ± 13% for C (p = 0.03), with no significant differences between groups. V̇O2max relative to FFM did not change significantly for any groups.

CONCLUSION

The change in V̇O2max paralleled the change in FFM for all groups, questioning the effect of HIT on V̇O2max over an 8-week period in youth athletes.

Effect of core training on athletic and skill performance of basketball players: A systematic review

A limited number of studies focus on the effect of core training on basketball players' athletic performance and skills. This systematic reviewaimed to comprehensively and critically review the available studies in the literature that investigate the impact of core training on basketball players' physical and skill performance, and then offer valuable recommendations for both coaches and researchers. Thedata collection, selection, and analysis adhered to the PRISMA protocol. English databases, including Ebscohost, Scopus, PubMed, Web of Science, and Google Scholar,were searched until September 2022. A total of eight articles were included, with four studies comparing the effects of core training versus traditional strength training or usual basketball training. All studies investigated the impact of core training on athletic performance. The findings revealed that core training can help players improve their overall athletic and skill performance, particularly in the areas of strength, sprinting,jumping, balance, agility, shooting, dribbling, passing, rebounding, and stepping. In addition, core training, particularly on unstable surfaces,as well as combining static and dynamic core training,improvebasketball players' athletic and skill performance. Despite the relativelylittle evidence demonstrating the effect of core training on endurance, flexibility, and defensive skills, this review demonstrates that it should be incorporated into basketball training sessions.

Reporting of Adverse Events in Muscle Strengthening Interventions in Youth: A Systematic Review

Clear definition, identification, and reporting of adverse event (AE) monitoring during training interventions are essential for decision making regarding the safety of training and testing in youths.

PURPOSE

To document the extent to which AEs, resulting from intervention studies targeting muscle strengthening training (MST) in youth, are reported by researchers.

METHODS

Electronic databases (CINAHL, PubMed, SPORTDiscus, and Web of Science) were searched for English peer-reviewed articles published before April 2018. Inclusion criteria were: (1) average age <16 years, (2) use of MST, (3) statement(s) linked to the presence/absence of AEs, and (4) randomized controlled trials or quasi-experimental designs. Risk of reporting bias for AEs followed recommendations by the Cochrane Collaboration group.

RESULTS

One hundred and ninety-one full-text articles were screened. One hundred and thirty met all MST criteria, out of which only 44 (33.8%; n = 1278, age = 12.1 [1.1] y) included a statement as to the presence/absence of adverse events. The 86 other studies (66.2%) included no such statement. Of the reporting 44 studies, 18 (40.1%) indicated one or more adverse events. Of the 93 reported adverse events, 55 (59.1%) were linked to training or testing.

CONCLUSIONS

Most MST studies in youth do not report presence/absence of adverse events, and when reported, adverse events are not well defined.

Effects of eight week core stability training on stable- and unstable-surface on ankle muscular strength, proprioception, and dorsiflexion in athletes with chronic ankle instability

BACKGROUND

Chronic ankle instability (CAI) is a common injury among athletes. Research has reported reduced dorsiflexion range of motion, impairment of proprioception, and decreased muscle strength of the ankle in people with CAI. The aim of this research was to examine the effects of 8-week core stability training on stable and unstable surfaces on ankle muscular strength, proprioception, and dorsiflexion range of motion (ROM) in athletes with CAI.

METHODS

Thirty-six athletes with CAI (age 22.42 ± 2.76 years; height 169.11 ± 3.52 cm; weight 68.46 ± 2.75 kg) participated in this study. They were divided into three groups: unstable-surface group (UG) (n = 12), stable-surface group (SG) (n = 12), and control group (CG) (n = 12). The UG and SG performed the core stability exercise protocol for 8 weeks, 3 sessions per week. The CG received their usual care and daily activities. Outcomes were measured pre-sessions and post-sessions.

RESULTS

The peak torque showed significant increases in the UG and SG compared with the CG during plantar flexion, dorsiflexion, inversion, and eversion (P < 0.05). There were also significant increases in UG compared with SG (P < 0.05). The proprioception showed significant decreases in UG compared with SG and CG (P < 0.05). The dorsiflexion ROM showed significant increases in UG and SG compared with CG. There were also significant increases in UG compared with SG (P < 0.05).

CONCLUSIONS

It seems that core stability exercises on trampoline surface helps improve the measured parameters in athletes with ankle instability. Therefore, this type of training is recommended as a therapeutic option for Individuals with CAI.

The core of performance in adolescent cricket pace bowlers: Trunk muscle stability, maybe, but not strength-endurance and thickness

Background

The trunk connects the upper and lower limbs and transfers energy during movement. Exploring the role of the trunk muscles in bowling performance affords us the opportunity to uncover potential mechanisms to improve bowling performance.

Objectives

To investigate the association between bowling performance and trunk muscle stability, strength-endurance and thickness in adolescent pace bowlers.

Methods

Adolescent pace bowlers participated in this cross-sectional study. Trunk muscle stability was measured using Sahrmann's Stability Scale, strength-endurance using the Bourbon Trunk Muscle Strength Test and thickness of the abdominal wall and lumbar multifidus muscles using ultrasound imaging.

Results

Forty-six pace bowlers with a mean age of 15.9 ±1.2 years participated. The average ball release speed was 109.2±11.8 km.h^-1. This measurement was higher in level four of stability than in level two (mean difference 22.2 ± SD 6.8 km.h^-1; p= .018). No link between ball release speed and strength-endurance could be found. Multiple correlations of moderate strength (r > 0.4) exist between ball release speed and absolute trunk muscle thickness with height and weight as confounding factors. The relationship between accuracy and the trunk muscle variables investigated in this study is weak.

Conclusion

Bowlers with better trunk muscle stability bowled faster than those with a lower level of trunk stability, irrespective of their age, height and weight. Trunk muscle thickness correlated with ball release speed; however, confounding factors such as height and weight play a role and therefore, findings need to be interpreted with caution.

IMPACTS OF BALANCE UNDER LOWER LIMB TRAINING

ABSTRACT Introduction How to scientifically improve the sports balance ability of table tennis players is a frequent question among current researchers. Increasing the explosive power and stability of the lower limbs to improve competitive performance is one of the main focuses of current research. Objective Analyze the impacts caused by lower limb training on the balance ability of table tennis players. Methods Junior table tennis students from a university were randomly divided into experimental and control groups. The control group had routine training while the experimental group had a protocol with lower limb training added. Results There was a statistical difference in the forward jump from 225.268 (± 13.229) cm before the experiment to 269.127 (± 9.331) cm after the experiment, and the left and right inclined jump values also followed this pattern after the experiment. The standing jump distance of the control group increased from 220.077 (± 21.124) cm before the experiment to 258.122 (± 15.1301) cm after the experiment. Conclusion Habitual sports training positively impacts table tennis players, but the effect is relatively slow and has low training efficiency. The lower limb strength training scheme proposed in this study showed improved sporting efficiency in athletes and expressive gains in their lower limb strength, positively impacting dynamic balance ability. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESEARCH ON THE MAIN METHODS OF CORE STRENGTH TRAINING IN SPRINTERS

ABSTRACT Introduction With the development of increasingly competitive sports, coaches began experimenting with new methods for training athletes. Although among the most explored training methods is core strength training, a set of muscle groups that stabilize the trunk and hips, there are few studies on the effectiveness of this training dedicated to sprinters. Objective This paper investigates the training method of sprinters based on core strength training, studying the method and its influence on athletes’ performance. Methods Sixteen athletes with similar technical levels and physical fitness were selected, and professional coaches were invited to test the training samples. The athletes were randomly assigned to the experimental and control group (8 in each). The experimental group received core strength training for eight weeks, while the control group received general training. Results Off-core training affected the ankle joint angle of the support leg and the ankle joint angle of the swing leg (P < 0.01). After eight weeks of training, the performance of both groups improved without considerable differences. The high jump results of the athletes in the experimental group also improved compared to the previous training. Conclusion The physical function of athletes can be improved through core strength training to improve the sprinters’ competitive level and technical ability. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Neuromuscular and balance adaptations following basketball-specific training programs based on combined drop jump and multidirectional repeated sprint versus multidirectional plyometric training

Multidirectional jumping and repeated sprint ability are crucial performance factors in basketball. The main aim of this investigation was to examine the neuromuscular performance and body balance adaptations following basketball-specific combined training programs based on drop jump and multidirectional repeated sprint versus multidirectional plyometric training. Forty-two professional basketball male players participated in the current investigation and were randomly assigned to three groups: a combined group (COMB; n = 14), a multidirectional jump group (MJG; n = 14) and an active control group (CON; n = 14). The COMB and the MJG groups completed the 8-week training programs with two weekly sessions while the CON continued their usual training. The static and dynamic balance tests, the repeated sprint ability test (IRSA5COD), the T-change of direction (CoD) test, the vertical jump tests, the five time-jump test (FJT) were performed by participants before and after the intervention period. The results showed a significant main effect of time with remarkable improvements at the end of the intervention (P < 0.001, effect size small/moderate) except the physiological parameters for IRSA5COD. Only, significant group × time interactions for body balance, T-CoD test, IRSA5COD (total time and best time), and jump tests were found (P < 0.001, effect size from trivial to moderate). Bonferroni corrected post-hoc tests revealed significantly greater improvement in favor of COMB compared to MJG for body balance, CoD and IRSA5COD (P < 0.005, effect size small/moderate). Otherwise, no significant differences between COMB and MJG concerning jump performances were found. Combined drop jump and multidirectional repeated sprint training program lead to significantly better neuromuscular performance, body balance and CoD in professional basketball players when compared with an usual training.

INFLUENCES OF ABDOMINAL CORE STRENGTHENING ON EXPLOSIVE STRENGTH IN MARTIAL ARTS ATHLETES

ABSTRACT Introduction: Martial arts demand a high-stability from their athletes, allied to a fast speed in complex movements. These characteristics have been shown to increase in other sports with the strengthening of the abdominal core of their athletes, and it is believed that martial arts practitioners could also benefit from this additional exercise. Objective: Explore the influences of abdominal core strengthening on explosive strength in martial arts athletes. Methods: Twenty martial arts athletes were selected and randomly divided between the experimental and control group. The experimental group did abdominal core strength training associated with traditional physical training, while the control group practiced only traditional physical training. After the experiment, new physical tests were performed, comparing the pre and post results regarding peak torque, explosive strength, and impact explosive strength of martial arts athletes. Results: The relative strike force of the straight fist in the experimental group increased from 25.75 to 31.89 after the experiment; the relative strike force to the lower limbs increased from 37.64 to 47.00 after the experiment (p<0.05). Conclusion: After the executed strength training, the athletes’ extensor peak torque and impact explosive strength indexes were significantly enhanced, evidencing the improvement of the explosive strength of martial arts athletes. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

INFLUENCE OF ATHLETICS ON MUSCLE COMPOSITION AND BALANCE OF STUDENTS

ABSTRACT Introduction The physical quality of college students decreases annually, a problem that physical education teachers should consider. Athletics can exercise the body’s musculature integrally and improve young college students’ physical and psychological abilities. Objective Analyze the influence of athletics on the muscle composition and hemodynamic balance of students. Methods In a given university 70 volunteers were randomly selected and divided into experimental and control classes, with 35 students each. The experimental class chose a gymnastics course, while the control class performed athletic activities represented by running. Results Under continuously increasing exercise duration and intensity, the athletes gradually shifted from aerobic to anaerobic exercise, so that muscle oxygen saturation gradually decreased. The dynamic balance ability of the students in the experimental class was greatly improved compared to the control class, reaching a balanced state. Conclusion The athletic program proposed in this paper can promote the adjustment of athletes’ blood oxygen saturation, increase muscle oxygen delivery capacity, and exercise endurance, and fully promote fitness progress in the students. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

Correlations between core muscle strength endurance and upper-extremity performance in adolescent male sub-elite handball players

Handball is an Olympic contact sport with high physical, tactical, and technical demands by the players. Out of the different techniques, throwing is the most important one to be able to score. The objective of the study was to investigate the relationships between core muscle strength endurance (Bourban test: ventral, dorsal and lateral chain) and shoulder mobility/stability (Upper Quarter Y Balance test [YBT-UQ]) as well as throwing velocity in adolescent male sub-elite handball players (N = 32, age: 17.1 ± 0.7 years, height: 181.8 ± 6.3 cm, BMI: 24.6 ± 4.9 kg/m2). All participants were free of injuries at least two weeks prior to the study, experienced (training experience: 8.5 ± 3.3 years) handball players who were tested mid-season in the evening of one of their training sessions. Pearson correlations were calculated for core muscle strength endurance with (a) shoulder mobility/stability and (b) throwing velocity. The throwing arm reach displayed significant correlations (both p &lt; 0.05) between the Bourban test (ventral chain) and the inferolateral reach direction (IL) of the YBT-UQ (r = 0.41) as well as the composite score (CS) (r = 0.34). For the dorsal chain, significant correlations (all p &lt; 0.01) were found for the medial (MD) (r = 0.42) and IL (r = 0.61) reach direction as well as the CS (r = 0.51). For the right but not the left side of the lateral chain, significant correlations (both p &lt; 0.05) were detected for the IL reach direction (r = 0.40) and the CS (r = 0.35). For the non-throwing arm reach, significant correlations were found between the ventral chain and the MD reach direction (r = 0.53, p &lt; 0.01) as well as the CS (r = 0.31, p &lt; 0.05). For the dorsal chain, significant correlations (all p &lt; 0.01) were found for the MD (r = 0.47) and IL (r = 0.44) reach direction as well as the CS (r = 0.41). For the lateral chain, significant correlations were detected for the MD (left and right side: r = 0.49, p &lt; 0.01) and IL (left and right side: r = 0.35, p &lt; 0.05) reach direction as well as the CS (left and right side: r = 0.37, p &lt; 0.05). The dorsal chain but not the ventral and lateral chain of the Bourban test showed a significant correlation with throwing velocity (r = 0.33, p &lt; 0.05). Our results indicate that better core muscle strength endurance is associated with better shoulder mobility/stability as well as partially higher throwing velocity of adolescent male sub-elite handball players. Therefore, practitioners should integrate core muscle strength endurance exercises into the training routines to improve upper-extremity performance of this target group.

Effects of a 6 week core strengthening training on measures of physical and athletic performance in adolescent male sub-elite handball players

The objective was to investigate the effects of a 6-week core strengthening training within the regular handball training sessions compared to regular handball training only. Male sub-elite handball players were randomly assigned to an intervention (INT: n = 13; age: 16.9 ± 0.6 years) or a control (CON: n = 13; age: 17.2 ± 0.8 years) group. The INT group performed the "big 3" core exercises cross curls-up, side bridge (both sides), and the quadrupedal stance ("birddog exercise") triweekly for 20-30 min while the CON group conducted regular handball training only. Pre- and post-training assessments included measures of muscular endurance (Closed Kinetic Chain Upper Extremity Stability Test [CKCUEST] and the Bourban test), shoulder mobility/stability (Upper Quarter Y Balance [YBT-UQ] test), and throwing velocity. The ANCOVA revealed significant differences between means in favour of the INT group for the dorsal chain (p < 0.001,η p 2 = 0.46) and the lateral chain (left side: p = 0.015,η p 2 = 0.22; right side: p = 0.039,η p 2 = 0.17) of the Bourban test, the composite score (p = 0.024,η p 2 = 0.20) of the throwing arm reach and the inferolateral reach direction (p = 0.038,η p 2 = 0.17), and the composite score (p = 0.027,η p 2 = 0.19) of the non-throwing arm reach of the YBT-UQ. However, performance in the CKCUEST and throwing velocity did not show any group-specific changes. Therefore, 6 weeks of core strengthening training were effective in improving some components of physical but no handball-specific athletic (i.e., throwing velocity) performance in adolescent male sub-elite handball players. Practitioners may still opt for this training regimen when stimulus variability is sought or when a low load/low movement approach (e.g., during rehabilitation) is favoured.

Assessment of the Speed and Power of Push-Ups Performed on Surfaces with Different Degrees of Instability

(I) Training in unstable conditions, with different elements, platforms, or situations, has been used because there is a significant increase in muscle activation, balance, proprioception, and even sports performance. However, it is not known how the devices used are classified according to performance variables, nor the differences according to instability experience. (II) This study aims to analyze the differences in power and speed in push-ups with different situations of instability in trained and untrained male subjects. Power and speed in push-up exercise were analyzed in 26 untrained and 25 trained participants in 6 different situations (one stable and five unstable) (1) stable (PS), (2) monopodal (PM), (3) rings (PR), (4) TRX^® (PT), (5) hands-on Bosu^® (PH) (6) feet on Bosu^® (PF). The variables were analyzed using a linear position transducer. (III) The best data were evidenced with PS, followed by PR, PM, PT, PH and PF. The trained subjects obtained better results in all the conditions analyzed in mean and maximum power and speed values (p < 0.001). The decrease in these variables was significantly greater in the untrained subjects than in the trained subjects in the PR situation (8% and 18% respectively). In PF there were differences between groups (p < 0.001), reaching between 32-46% in all variables. The difference between the two groups was notable, varying between 12-58%. (IV) The results showed a negative and progressive influence of instability on power and speed in push-ups. This suggests that instability should be adapted to the subject's experience and is not advisable in untrained subjects who wish to improve power.

Relationship between Moderate-to-Vigorous Physical Activity with Health-Related Physical Fitness Indicators among Pakistani School Adolescents: Yaali-Pak Study

Background

The current study is the foremost study exploring the relationships between moderate-to-vigorous physical activity and health-related physical fitness indicators among 12-16-year-old adolescents of the South Punjab region of Pakistan.

Methods

The researcher adopted the cross-sectional research design for the study. A total of 2970 participants (1477 boys and 1493 girls) aged adolescents from South Punjab, Pakistan, completed health-related physical fitness indicators measuring strength, endurance, and aerobic capacity through a hand-grip strength test, modified pull-up test, plank test, and 20-m shuttle run test, and physical activity were subjectively assessed by International Physical Activity Questionnaire Short Form (IPAQ-SF). Linear regression models were used to explore the between moderate-to-vigorous physical activity (MVPA) with health-related physical fitness indicators.

Results

Positive associations were observed between hand-grip strength (p < 0.001), modified pull-up (p < 0.001), plank exercise (p < 0.001), and 20-m shuttle run test (p < 0.001), with MVPA. The gender-specific comparison also indicated a significant (p < 0.001) and positive relationship. The results revealed that as MVPA increases, body composition, muscular strength, core muscular endurance, and aerobic capacity could improve in both genders.

Conclusions

MVPA appears to be an effective and reliable predictor of health-related physical fitness among school adolescents.

Impact of combined versus single-mode training programs based on drop jump and specific multidirectional repeated sprint on bio-motor ability adaptations: a parallel study design in professional basketball players

Background

Jumping and specific multidirectional repeated sprint ability are important in basketball. The objective of this study was to assess the contributions of 8-week combined versus single-mode training programs based on drop jump (DJ) and specific multidirectional repeated sprint (MRSA) on repeated sprint ability performances, body balance and lower limbs power in male professional basketball players.

Methods

This study followed a randomized parallel study design. Fifty-two professional male basketball players from the Tunisian first division participated in this study. The players were randomly assigned to 4 groups: DJ group (JG; n = 13), MRSA group (RSG; n = 13), combined group (COMB; n = 13) and an active control group (CON; n = 13). The JG, RSG and COMB groups completed the 8-week training programs with 2 sessions per week while the CON continues their regular basketball training. Training volume was similar between groups all over the experimental period. Before and after the intervention, the four groups were evaluated for the stork test, Y-balance test, the repeated sprint ability test (IRSA_5COD), the squat jump (SJ) and countermovement jump (CMJ) tests, the single leg drop jump test, the five time-jump test and T—change of direction (CoD) test.

Results

All measures displayed significant main effect, (medium/small) magnitude (effect size) improvements for time (post-test > pre-test) except the physiological parameters for IRSA_5COD. Significant time × group interactions were revealed for body balance, T test, IRSA_5COD (total time and best time) and jump tests (vertical/horizontal). Bonferroni corrected post-hoc tests revealed significant greater improvement in favor of RSG and COMB compared to JG for body balance, CoD and IRSA_5COD. Moreover, greater improvement in CMJ, SJ and single leg DJ in favor of JG compared to the RSG. In addition, a greater CoD improvement was observed in favor of COMB when compared to the RSG.

Conclusion

Combined and single-mode training programs based on DJ and MRSA contributed to a significantly better performance in specific basketball physical fitness parameters with results favoring combined interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-022-00551-w.

Effects of core training on dynamic balance stability: A systematic review and meta-analysis

Core stability has a strong relationship with dynamic balance stability (DBS). The purpose of this review with meta-analysis was to analyse the effects of core training programmes from different studies on DBS. A literature search was performed using different databases. Subgroups analyses on duration, training frequency, total sessions, chronological age, training status, equipment and movements were performed. A random-effects model for meta-analyses was used. Thirteen studies were selected for the systematic review and 10 for the meta-analysis, comprising 226 participants. A moderate effect was noted for core training on DBS (p < 0.001; ES = 0.634). Greater DBS improvements were found in core training interventions with ≤6 weeks (ES = 0.714), after high volume (ES = 0.787) and more frequent interventions (ES = 0.787), as well as in younger participants (ES = 0.832). In addition, body weight exercises may be better than med ball, swiss ball or band resisted exercises. Core training improves DBS among athletes and a non-trained population, creating a more solid stable base that allows better lower extremity movements. This could be more effective considering different modulators ≤6 weeks intervention, >2 sessions per week, >17 total sessions, body weight core programmes and applied to ≤18.0 years old.

CORE VS PLYOMETRIC TRAINING EFFECTS ON DYNAMIC BALANCE IN YOUNG MALE SOCCER PLAYERS

ABSTRACT Introduction: Today, different types and volumes of strength training are used to increase the performance of athletes. However, the effect of this training on dynamic balance in young soccer players is a matter of curiosity. Objective: The purpose of this study is to determine the effects of core and plyometric training on dynamic balance in young male soccer players. Materials and Methods: Eighteen male soccer players between 17 and 18 years of age participated in the study voluntarily. Subjects were randomly separated into three groups: core training group (C, n=6), plyometric training group (P, n=6), and control group (Con, n=6). Group C and P subjects participated in the determined training programs, in addition to soccer training, two days a week for eight weeks. The Con group only continued their soccer training. The Y-balance test (before and after eight weeks) was applied to determine the balance performance of the subjects. Results: After eight weeks of core training, significant differences in anterior (ANT) and posteromedial (PM) balance performance on the dominant side and in ANT, PM, and posterolateral (PL) balance performance on the non-dominant side were observed in group C subjects. The PL and PM balance performance of group P subjects after plyometric training was found to be significantly different on both sides. Conclusion: As a result, it was determined that applying core and plyometric training in addition to soccer training increases dynamic balance. We recommend that trainers and coaches use core and plyometric exercises in their training, as these programs will provide a positive performance increase in balance and gains in muscle strength. Level of Evidence III; Prospective comparative study.

Effects of a SMART Goal Setting and 12-Week Core Strength Training Intervention on Physical Fitness and Exercise Attitudes in Adolescents: A Randomized Controlled Trial

This study aimed to analyze the impacts of a 12-week core strength training (CST) and goal-setting (GS) program on the core endurance, agility, sprinting, jumping, grip strength, and exercise attitude in a group of adolescents. This study followed a randomized parallel design in which 362 adolescents (age: 14.5 ± 1.07 years; body mass index: 19.82 ± 3.64) were allocated to a GS (n = 89), CST (n = 92), or GS + CST (n = 90) program or to a control group (n = 91). Participants were assessed two times (baseline and postintervention) for the following tests: (i) 50 m dash, (ii) grip strength, (iii) long jump, (iv) 1000 m running for boys and 800 m for girls, (v) core endurance, and (vi) exercise attitude. Significant differences (p < 0.05, η2p = 0.035−0.218) were found between the four groups of the six components of physical fitness and the three components of attitude toward exercise (target attitudes, behavioral habits, and sense of behavioral control). Between-group analysis revealed that the GS + CST had significant advantages (p < 0.05) over the CON in terms of the 50 m dash (Cohen’s d = 0.06), grip strength (Cohen’s d = 0.19_left, 0.31_right), 800/1000 m running (Cohen’s d = 0.41), core endurance (Cohen’s d = 0.95), and sense of behavioral control (Cohen’s d = 0.35). Between-group analysis also revealed that the CST had significant advantages over the CON in terms of grip strength (Cohen’s d = 0.27_left, 0.39_right), 50 m (Cohen’s d = 0.04), long jump (Cohen’s d = 0.21), 800/1000 m (Cohen’s d = 0.09), and core stability (Cohen’s d = 0.63), which were significantly different from CON (p < 0.05). GS differed from CON only on 50 m (Cohen’s d = 0.02) and core stability (Cohen’s d = 0.13) with a small effect (p < 0.05). We conclude that the combined intervention of GS and CST is more effective in promoting fitness in adolescents, i.e., GS + CST > CST and GS + CST > GS.

The effects of balance and core stability training on postural control in people with visual impairment: A systematic review

Visual impairment is one of the most common functional impairments that considerably affects the postural control process and the ability to maintain balance. The purpose of this study was to perform a systematic review concerning the effects of balance and core stability training on postural control in individuals who are visually impaired. This article comprehensively reviewed studies on balance in individuals who are blind from the following databases: PubMed, Embase, Web of Science, and Scopus from 2007 to 2021. Inclusion and exclusion criteria were people who were blind or visually impaired (acquired and congenital), men and women, all ages, and at least 6 weeks balance or core stability training program. Twelve articles were included in this review. Individuals with visual impairment and blindness from all ages were included in this study. According to this review, all balance and core stability protocols in this article have positive effects on balance and postural control for individuals with visual impairments. Therefore, balance and core stability intervention for at least 6 weeks is one of the more well-established protocols for improving balance and postural control in people with visual impairment and can have a positive impact in risk of falling regardless of age, gender, or severity of visual impairment.

Short-term effects of on-field combined core strength and small-sided games training on physical performance in young soccer players

This study aimed to compare the effects of 6-weeks combined core strength and small-sided games training (SSG_core) vs. small-sided games (SSG) training on the physical performance of young soccer players. Thirty-eight amateur soccer players (age: 16.50 ± 0.51 years) were randomly assigned to either a SSG_core (n = 20) or a SSG group (n = 18). The SSG_core group performed upper and lower body core strength exercises combined with SSG including 2-, 3- and 4-a-sided soccer games third a week. The SSG group performed only the SSG periodization. Baseline and after the 6-week training period the Yo-Yo Intermittent Recovery Test level 1 (YYIRTL-1), 5–20-m sprint test, countermovement jump (CMJ), squat jump (SJ), triple-hop distance (THD), zigzag agility with ball (ZAWB) and without ball (ZAWOB), three corner run test (TCRT) and Y-balance test. The SSG_core group demonstrated meaningful improvements in 20 m sprint time (SSG_core: -9.1%, d = 1.42; SSG: -4.4%, d = 0.76), CMJ (SSG_core: 11.4%, d = 2.67; SSG: -7.7%, d = 1.43), SJ (SSG_core: 12.0%, d = 2.14; SSG: 5.7%, d = 1.28), THD (SSG_core: 5.0%, d = 1.39; SSG: 2.7%, d = 0.52) and TCRT (SSG_core: -3.7%, d = 0.69; SSG: -1.9%, d = 0.38). Furthermore, the SSG_core group demonstrated meaningfully higher improvement responses in both leg balance score (d = ranging from 2.11 to 2.75) compared with SSG group. These results suggest that the inclusion of core strength training to a SSG periodization is greatly effective to improve speed and strength-based conditioning in young soccer players.

Effects of a 6-week core stabilization training program on dynamic balance and trunk stabilization endurance of horse riders

The purpose of this study was to examine the effectiveness of a 6-week core stabilization training program (CSTP) in improving dynamic balance and back-extensor endurance of horse riders; and develop a measurement tool in assessing the dynamic postural stabilization endurance for horse riders. Twelve male horse riders (age: 23.58 ± 1.93 years; height: 165.09 ± 4.60 cm; weight: 56.53 ± 4.75 kg; experience in horse racing: 1.75 ± 0.34 years) completed 12 training sessions in 6 weeks. Subjects performed the CSTP with two progressions. CSTP started with the basic consciousness activation exercises, and then eliminated visual feedback in dynamic balance task on unstable surfaces and finished with switching the center of gravity. Moderate-to-large difference was demonstrated in the Y-Balance test scores for right leg (102.81 ± 8.32 vs 106.471 ± 4.35 cm, d = 0.55, 95% CL 0.00 to 1.08) and left leg (102.04 ± 3.20 vs 106.29 ± 3.62 cm, d = 1.25, 95% CL 0.41 to 2.05) following 6 weeks CSTP. However, trivial to small differences was reported between left and right leg in pre (d = 0.12, 95% CL − 0.49 to 0.73) and post 6-week CSTP (d = 0.04, 95% CL − 0.69 to 0.78). Biering–Sørensen test (BST) shows largely greater performance after 6-week CSTP (98.3 ± 30.1 vs 131.8 ± 19.0 s, d = 1.33, 95% CL 0.54–2.09). A novel measurement, Swiss ball four-point kneeling test was shown to be correlated with the change in BST (r = 0.633).

Effect of core muscle strengthening on throwing velocity in cricket players in Pakistan: a 6-week randomized controlled trial

BACKGROUND

During fielding throwing ball with more velocity and accuracy towards the stump to reduce score and produce an out of the opponent team. Core is the power house of the body. Core training improves the strength of trunk muscles and allows the players to kick, throw, pull, and push with greater force.

AIM

This study was conducted to determine the effects of core muscle strengthening on throwing velocity in cricket players that whether core muscle strengthening would help the cricket players to improve their throwing velocity and core endurance.

METHODS

A 6 weeks randomized controlled trial in which Ninety-eight male cricket players participated and divided into strength training (interventional) and non-strength training (control group). Interventional group followed general core strengthening exercise protocol for six weeks for 3 days a week. Assessment of the players include core assessment test (back extension, supine forward flexion test, prone bridge test). Time and throwing velocity was noted by stop watch and radar gun in km/hr respectively at baseline and after 6 weeks of core training. Control group did not follow any exercise program but continued their usual cricket training.

RESULTS

Mean age of interventional group was 20.4±4.9 years and control group was 21.6±3.4 years. The mean BMI of interventional and control group was 22.4±2.7 kg/m2 and 21.8±2.1 kg/m2, respectively. Comparing both groups, in between group analysis stregnth training group results showed statistically highly significant increase p<0.001 in compoments 'throwing velocity, back extension, supine flesion , right plank lateral, left lateral planl and isometric prone plank' than non strengthing group. In within group analysis, strength group had improved as compared to the control group which showed no improvement.

CONCLUSIONS

There is significant increase in throwing velocity and core endurance with six weeks general core stregthening in male cricket players.

Effects of bodyweight neuromuscular training with and without instability on balance control in active universitarians

The purpose of this study was to analyse the effects of a nine-week unstable vs stable bodyweight neuromuscular training programme on balance control. Seventy-seven physically active universitarians were randomly distributed into an unstable training group (UTG), a stable training group (STG), and a control group (CG). The intervention was conducted three times a week for nine weeks. Pre- and post-intervention assessments included static balance control under an unstable surface (eyes open (EOFS), eyes closed (ECFS), challenging visual-vestibular system (CVVS)), assessed as centre-of-pressure fluctuations with a force plate. A mixed ANOVA was performed to test the within- and between-subjects factors. After the intervention, no significant differences were found between groups. All groups presented significant improvements in balance measurements in EOFS (p = 0.01), ECFS (p = 0.01; p = 0.02), and CVVS (p = 0.01) conditions. The training groups tended to have significantly better balance control (antero-posterior) than the CG on EOFS. In the CVVS condition, the UTG tended to have better balance control than the CG. There was no overall significant training advantage gained by using unstable or stable surfaces in terms of the improvement in static balance control in active universitarians. Both training groups exhibited similar training adaptations.

Unilateral Plyometric Training is Superior to Volume-Matched Bilateral Training for Improving Strength, Speed and Power of Lower Limbs in Preadolescent Soccer Athletes

This study compared the effects of unilateral and bilateral plyometric training on strength, sprint performance and lower limb power. Sixty-eight preadolescent soccer athletes were randomly assigned to a unilateral plyometric training group (n=23), a bilateral plyometric training group (n=23) and a control group (n=22). Both plyometric training groups trained with equal volumes of unilateral or bilateral exercises for 15 minutes in each session, at which time the control group performed soccer-specific drills. Plyometric exercises were executed twice weekly for 10 weeks during the competitive season. The following tests were performed before and after the intervention: single-leg and double-leg countermovement jump, squat jump, horizontal jumps in different directions, maximal isometric strength of quadriceps and hamstrings, sprint performance, agility and balance. Unilateral plyometric training resulted in greater improvements compared to the control group in the following variables: hamstrings strength (ES: 0.91, p=0.037), 5m sprint time (ES: 0.93, p=0.004), single-leg countermovement jump (ES: 0.90, p=0.006), single- and double-leg squat jump (ES: 0.87, p=0.030 and ES: 0.73, p=0.067, respectively) and single-leg hop performance (ES: 1.01, p=0.004). The only tests where there was an improvement of BPT compared with the CG were the single-leg and double leg SJ (ES: 0.76, p=0.026; ES: 0.70, p=0.050). Quadriceps strength, side hop test, double-leg horizontal jump test, flamingo balance test and modified agility T-test were equally improved in all three groups (p<0.001). In conclusion, unilateral lower-limb plyometric training is more effective in increasing muscle strength and power in preadolescent soccer players when compared to bilateral training or soccer training alone.

The effect of static and dynamic core exercises on dynamic balance, spinal stability, and hip mobility in female office workers

Objectives

This study aims to compare the effect of static and dynamic core exercises in terms of dynamic balance, spinal stability, and hip mobility in female office workers.

Patients and methods

Between May 2018 and June 2018, a total of 34 women (mean age 36.4±6.5 years; range, 28 to 54 years) who worked for a bank and exercised in the fitness center of the work place were recruited. The women were divided into two groups including 17 women in each as static and dynamic core groups and administered sessions of 20 to 30 min twice a week for six weeks. Both groups were tested for dynamic balance (Y-balance test), spinal stability (functional reach test), and hip mobility (active flexion and extension) before and after six weeks of exercise.

Results

A statistically significant improvement was found in both groups between the pre- and post-test results in terms of spinal stability, hip mobility, and dynamic balance (p<0.05). The only exception was the right and left leg anterior balance in the static core group. Dynamic core exercises seemed to be more effective than static core exercises in improving the right and left leg anterior balance. There were no statistically significant differences between the groups in terms of spinal stability, hip mobility, and dynamic balance according to the mean absolute change (p>0.05).

Conclusion

Our study results indicate that both types of exercises are effective in improving dynamic balance, spinal stability, and hip mobility in female office workers. Therefore, the expected benefits from core exercises are to enhance dynamic balance, spinal stability, and hip mobility. Female workers can perform both types of exercises safely and effectively.

Effects of Equal Volume Heavy-Resistance Strength Training Versus Strength Endurance Training on Physical Fitness and Sport-Specific Performance in Young Elite Female Rowers

Strength training is an important means for performance development in young rowers. The purpose of this study was to examine the effects of a 9-week equal volume heavy-resistance strength training (HRST) versus strength endurance training (SET) in addition to regular rowing training on primary (e.g., maximal strength/power) and secondary outcomes (e.g., balance) in young rowers. Twenty-six female elite adolescent rowers were assigned to an HRST (n = 12; age: 13.2 ± 0.5 yrs; maturity-offset: +2.0 ± 0.5 yrs) or a SET group (n = 14; age: 13.1 ± 0.5 yrs; maturity-offset: +2.1 ± 0.5 yrs). HRST and SET comprised lower- (i.e., leg press/knee flexion/extension), upper-limbs (i.e., bench press/pull; lat-pull down), and complex exercises (i.e., rowing ergometer). HRST performed four sets with 12 repetitions per set at an intensity of 75–95% of the one-repetition maximum (1-RM). SET conducted four sets with 30 repetitions per set at 50–60% of the 1-RM. Training volume was matched for overall repetitions × intensity × training per week. Pre-post training, tests were performed for the assessment of primary [i.e., maximal strength (e.g., bench pull/knee flexion/extension 1-RM/isometric handgrip test), muscle power (e.g., medicine-ball push test, triple hop, drop jump, and countermovement jump), anaerobic endurance (400-m run), sport-specific performance (700-m rowing ergometer trial)] and secondary outcomes [dynamic balance (Y-balance test), change-of-direction (CoD) speed (multistage shuttle-run test)]. Adherence rate was >87% and one athlete of each group dropped out. Overall, 24 athletes completed the study and no test or training-related injuries occurred. Significant group × time interactions were observed for maximal strength, muscle power, anaerobic endurance, CoD speed, and sport-specific performance (p ≤ 0.05; 0.45 ≤ d ≤ 1.11). Post hoc analyses indicated larger gains in maximal strength and muscle power following HRST (p ≤ 0.05; 1.81 ≤ d ≤ 3.58) compared with SET (p ≤ 0.05; 1.04 ≤ d ≤ 2.30). Furthermore, SET (p ≤ 0.01; d = 2.08) resulted in larger gains in sport-specific performance compared with HRST (p < 0.05; d = 1.3). Only HRST produced significant pre-post improvements for anaerobic endurance and CoD speed (p ≤ 0.05; 1.84 ≤ d ≤ 4.76). In conclusion, HRST in addition to regular rowing training was more effective than SET to improve selected measures of physical fitness (i.e., maximal strength, muscle power, anaerobic endurance, and CoD speed) and SET was more effective than HRST to enhance sport-specific performance gains in female elite young rowers.

Effect of a Six-Week Core Conditioning as a Warm-Up Exercise in Physical Education Classes on Physical Fitness, Movement Capability, and Balance in School-Aged Children

Whether the implementation of feasible, equipment-free, and simple core exercises in warm-up routines in physical education classes for school-aged children is beneficial remains unclear. Therefore, this study investigated the effects of a core conditioning in the warm-up routine of physical education classes on trunk muscular endurance, movement capability, and flexibility in this population. In these pre- and post-test control group experiments, 52 healthy, school-aged children (aged 10-11 years) were cluster randomized allocated to either the dynamic core exercise (DCE) group or general physical education (GPE) group. The DCE group performed a 10-min core exercise routine twice per week for six consecutive weeks; the GPE group performed traditional physical education warm-up exercises regularly. The children were assessed by conducting the trunk muscular endurance test (i.e., dynamic curl-up, static curl-up, plank, and lateral plank), functional movement screen (FMS), and single-leg balance test before and after the intervention. At the end of the intervention, the DCE group demonstrated a significant effect on trunk muscular endurance, movement capability (i.e., FMS scores), flexibility, and balance (each p < 0.001, effect size: 0.38-1.3). Furthermore, the DCE group showed significant improvements in all outcome measurements compared with the GPE group (p < 0.05, effect size: 0.29-1.68). These data may provide a reference for incorporating additional core stability exercises in the warm-up routine of physical education classes in school-aged children in the future.

The Increased Effectiveness of Resistance Training on Unstable vs. Stable Surfaces on Selected Measures of Physical Performance in Young Male Soccer Players

Sanchez-Sanchez, J, Raya-González, J, Ramirez-Campillo, R, Chaabene, H, Petisco, C, and Nakamura, FY. The increased effectiveness of resistance training on unstable vs. stable surfaces on selected measures of physical performance in young male soccer players. J Strength Cond Res XX(X): 000-000, 2020-To examine the effects of 10-week (2/wk) resistance training on stable vs. unstable surfaces on selected measures of physical performance in young male soccer players, national-level U19 players participated in this study. They were randomly allocated to an unstable resistance training group (uRT, n = 27) or a stable resistance training group (sRT, n = 28). Before and after the training, horizontal jumping with dominant (Hop D) and nondominant leg (Hop non-D), repeated sprint ability (RSA best time [RSAbest] and RSA mean time [RSAmean]), change-of-direction (COD) speed (Illinois COD test), and aerobic endurance (YoYo Intermittent Recovery Test Level 1 [YoYo IR1]) were assessed. To establish the effects of the interventions on the dependent variables, a 2 (group: uRT and sRT) × 2 (time: pre, post) analysis of variance with repeated measures on time was computed. A significant main effect of time was observed for Hop non-D, RSAbest, and RSAmean (p = 0.003-0.06, effect size [ES] = 0.06-0.15). Furthermore, significant group × time interactions were shown for RSAbest (p = 0.007, ES = 0.13) and RSAmean (p = 0.002, ES = 0.2). Post hoc analysis revealed significant pre- to post-training improvements for RSAbest (p = 0.002, ES = 0.35) and RSAmean (p = 0.0002, ES = 0.36) in the uRT. In the sRT, however, no significant pre-post performance changes were observed in RSAbest and RSAmean. In conclusion, 10 weeks of an in-season resistance training on unstable conditions in addition to regular soccer training was effective in improving repeated-sprint ability performance in youth male elite soccer players including maximal linear sprinting and the ability to perform repeated sprint.

Effect of core strength training on balance, vertical jump height and throwing velocity in adolescent male handball players

BACKGROUND

The aim of this study was to examine the effects of core strength training (CST) on dynamic balance and vertical jump height, and throwing velocity in handball players.

METHODS

Twenty male handball players (mean age 14.90±0.44 years) participated in this study. The players randomly divided into two groups as CST and control (CON) groups. Dynamic balance, vertical jump, and throwing velocity were measured before and after a six-week CST.

RESULTS

Significant differences were found at anterior (P=0.009) and posteromedial (P=0.017) directions of the Star Excursion Balance Test (SEBT) in only CST group. There were significant improvement in vertical jump height of participants compared to pre-test scores in both CST (P=0.047) and CON group (P=0.013). No significant difference was found for throwing velocity compared with pre-test in both groups. There were no significant differences in all parameters when CST and CON groups were compared (P>0.05).

CONCLUSIONS

The results of the present study indicated that a 6-week CST did not improve dynamic balance, vertical jump height and throwing velocity in adolescent male handball players. We believe that longer CST programs may provide significant benefits.

Effects of core stabilization exercises on pulmonary function, respiratory muscle strength, and functional capacity in adolescents with substance use disorder: Randomized controlled trial

BACKGROUND

Adolescent substance abuse is a serious and growing problem worldwide. The aim of this study was to investigate the effects of core stabilization exercises on pulmonary function, respiratory muscle strength, and functional capacity in adolescents with substance use disorder (SUD).

METHODS

This was a prospective randomized controlled trial. A total of 49 adolescent male patients with SUD were randomly assigned to either the exercise group (n = 25; mean age 16.6 years) or the control group (n = 24; mean age 16.7 years), for 6 weeks. All participants underwent a medical and behavioral therapy program 5 days a week for 6 weeks. The exercise group received five core stabilization exercises combined with deep breathing as a group training for 45 to 60 minutes, twice a week for 6 weeks, and the control group received recreational activities in addition to the usual care for 45 to 60 minutes, twice a week for 6 weeks. Spirometry, maximal inspiratory and expiratory pressures, and the 6-minute walk test were performed and measured at baseline and after training.

RESULTS

There were significant improvements in maximal inspiratory pressure (24.16 cm H₂ O; P < 0.0001), maximal expiratory pressure (30.28 cm H₂ O; P < 0.0001), forced vital capacity (5.80% predicted, P < 0.0001), forced expiratory volume in 1 second (7.34% predicted; P = 0.002), peak expiratory flow (13.32% predicted; P = 0.0003), forced expiratory flow 25%-75% (11.84% predicted; P = 0.027), and the 6-minute walking distance (65.84 m; P < 0.0001) in the exercise group compared with the control group.

CONCLUSIONS

Core stabilization exercise can improve pulmonary function, respiratory muscle strength, and functional capacity in adolescents with SUD.

Evaluation of the Bourban Trunk Muscle Strength Test Based on Electromyographic Parameters

(1) Background: The importance of a strong and stable trunk musculature is well known, but there is a lack of reliable, valid and objective test batteries with the necessary test economy, practicability and cost-benefit ratio. The aim of the present study was to evaluate the Bourban test for the validity of its exercise selection representing the ventral, right/left lateral and dorsal muscle chain. (2) Methods: 33 male sports students (24.1 ± 2.4 years, 181.6 ± 5.5 cm, 80.8 ± 7.3 kg) participated in the study. Median Frequency (MDF) and Mean Frequency (MNF) were calculated from the electromyographic signals and used to check whether fatigue of the suggested target musculature actually occurs during the different exercises and thus the exercise is representative for this part of the trunk. (3) Results: In all exercises significant fatigue was measured for MDF and MNF in the muscles working as agonists. (4) Conclusion: It can be stated that the Bourban trunk muscle strength test is a valid and economic test instrument for the evaluation of trunk strength (endurance). Compared to technically supported measuring systems, the Bourban test seems to be a flexible and cost-effective alternative for the broad mass.

The Training Effects of Foam Rolling on Core Strength Endurance, Balance, Muscle Performance and Range of Motion: A Randomized Controlled Trial

Self myofascial therapy via foam roller is a common technique used by many athletes and patients to aid recovery, improve range of motion (ROM) and prevent injury. Further, it is suggested that foam rolling improves core stability. However, research about the training effects of foam rolling on measures of core "strength endurance", muscle performance, balance and flexibility is limited. Forty recreationally active females and males (age: 18-48 yrs) were randomly assigned to a foam roll (FOAM, n = 14), a core stabilization (CORE; n = 12) and a control group (CG, n = 12). FOAM massaged their lower leg muscles (5 exercises) with the foam roll 2 times per week for 8 weeks while CORE was assigned to core stability training including 5 exercises. CG underwent no intervention. Applied tests for outcome measurements were the Bourban trunk muscle strength test (TMS), standing long jump (SLJ), single leg triple hop for distance (SLTH) test, Y-Balance test and stand and reach test. There was an interaction effect (time x treatment) for the dorsal TMS (p = 0.043), demonstrating greater improvements in CORE compared with FOAM and CG with no difference between FOAM and CG. For the stand and reach test a main effect for time (p < 0.001) and time x treatment interaction (p = 0.005) were found, indicating an increase in ROM in FOAM compared with CORE and CG with no difference between the latter. No significant effects were found for balance and muscle performance. An 8-week training with the foam roll is effective in increasing ROM in the stand and reach test without concomitant decreases in core "strength endurance", muscle performance and balance parameters. The core stabilization training was sufficient to improve performance in dorsal TMS test.

Effect of core training on dynamic balance and agility among Indian junior tennis players

BACKGROUND

The effect of core training on dynamic balance and agility has yet to be established in literature, especially among junior athletes.

OBJECTIVE

To investigate the effect of core training on dynamic balance and agility among Indian junior tennis players.

METHOD

Thirty junior tennis players from various parts of Delhi and the national capital region participated in the study. The study featured a pre-test/post-test experimental design. The subjects were divided into the experimental group (mean age = 15.20 ± 0.41, mean BMI = 20.23 ± 1.54) and the control group (mean age = 15.53 ± 1.06, mean BMI = 20.71 ± 1.53). The control group performed regular training, and the experimental group followed a five-week core training program along with regular training. The subjects were evaluated with t-test for agility and the Star Excursion Balance Test (SEBT) for dynamic stability.

RESULTS

A significant difference was found in the post-test values of agility (t-test p= 0.000) and dynamic balance using SEBT ((anterolateral; p= 0.00), (lateral; p= 0.02), (posterolateral; p= 0.00), (posterior; p= 0.00), (posteromedial; p= 0.01), (medial; p= 0.03), and (anteromedial; p= 0.03)] except in the anterior direction (p= 0.23)) between the experimental and the control group. The experimental group showed a significant difference in the pre- and post-test values of the t-test and SEBT except in the anterior direction.

CONCLUSION

Core training programs can be incorporated safely with players' regular training to improve their dynamic balance and agility, which can eventually lead to better performance.

Instability training, assessing the impact of level of difficulty on balance: A randomized clinical trial

BACKGROUND

Most human movements are executed while in a state of postural instability. For this reason, instability training is a highly-specific method that is intended to improve balance and postural control. This research aimed to determine the effect of instability training on the balance of individuals with similar baseline abilities, who initiated training within different stability conditions.

RESEARCH QUESTION

Does the level of difficulty with which instability training is performed determine improvements in balance?

METHOD

A two-arm randomized trial was undertaken, for which 22 and 21 participants were included in the experimental and control groups, respectively. The experimental group performed balance training on unstable surfaces and the control group implemented the same training on stable ground. The primary outcome was the Y-Balance Test (YBT); the Emery test, Functional Reach test, and platform measures were the secondary outcomes. Confidence intervals were set at 95% and Cohen's f statistic was used to estimate effect size.

RESULTS

Dynamic balance, as measured by the YBT, showed significant Time improvements in both groups for right (p <  0.001, f = 0.53) and left (p =  0.005, f=0.33) limbs. Similar results were found in the Emery test and Functional Reach test. No statistical Group and Time*Group interactions were found. None of the proposals modified the center of pressure excursions.

SIGNIFICANCE

Instability training is a safe and effective approach to enhance balance. However, the findings deduced that the level of difficulty (instability) with which participants with similar abilities initiate the training is not a determining factor in the balance improvements achieved. It follows that instability training may be either used as an alternative or as an additional method to train for balance on a stable ground.

Effects of Core Strength Training Using Stable and Unstable Surfaces on Physical Fitness and Functional Performance in Professional Female Futsal Players

The aim of this study was to assess the effect of core strength training performed on a stable surface (CTS) compared with core strength training performed on an unstable surface (CTU) on physical fitness (jump performance, sprint, and repeated sprint ability (RSA)) and quality of movement (Fundamental Movement Screen) in professional female futsal players. Fourteen professional female futsal players (mean age: 23.7 ± 5.1 years, age range: 18-28 years) were randomly assigned to a CTS (n = 7) or a CTU (n = 7) group. The intervention program was carried out 3 times a week over 6 weeks. Players of both groups performed the same four core-strengthening exercises. The only difference between the two interventions was that the CTU group performed all exercises (i.e., shoulder bridge, side bridge, prone plank, and crunch) on an unstable surface (Togu® Dyn-Air). Within-group analysis showed significant improvements (p < 0.001) in 10 m sprint performance from the pre- to post-test in the CTS (+4.37%) and CTU (+5.00%) groups. Players in both the CTS (+10.39%) and CTU (+11.10%) group also showed significant enhancement in the Functional Movement Screen total score, from the pre-test to post-test. In addition, a significant time effect was also observed for the CTU group in the relative score of the RSA test decreasing from the pre- to post-test (-30.85%). In the between-groups analysis, there were no significant differences between the core strength training groups (CTS vs CTU) in any variable. To conclude, sprint and Functional Movement Screen performance improved following CTS and CTU when conducted in combination with regular futsal training. In addition, CTU had limited benefit in RSA compared to CTS.

Effects of core stability training on throwing velocity and core strength in female handball players

BACKGROUND

This study investigated the effect of a six-week in-season core stability training (CST) intervention on maximal throwing velocity and core strength parameters.

METHODS

Twenty female handball players (23.4±4.4 years, 168.4±3.5 cm, and 66.9±9.2 kg) were randomized into a CST intervention group (N.=10) and a control group (CON, N.=10). Throwing velocity, maximal isometric strength (MIS) and endurance strength of the ventral, dorsal and lateral core muscle chains were measured before and after progressive, six-week core stability training in the CST group.

RESULTS

Core endurance of both lateral core muscle chains (LR: F=7.03, P=0.017; LL: F=6.31, P=0.022;) and MIS of the left lateral core muscle chain (LL: F=7.08, P=0.019) was significantly improved in CST compared to CON group after 6 weeks. Additionally, CST group significantly increased MIS of the lateral right core muscles (21%, P=0.042) and the ventral core endurance (35%, P=0.016) compared to baseline. Although both groups significantly increased throwing velocity of the jump throw after the intervention (CST 12%, P=0.001; CON 8%, P=0.009), throwing velocity of the standing throw remained unchanged.

CONCLUSIONS

A six-week CST intervention effectively increased the isometric strength and endurance of selected core muscles but did not significantly enhance throwing velocity compared to standard training.

Effects of core strength training combined with Tai Chi Chuan for the musculoskeletal system and cardiopulmonary function in older adults: A study protocol for a randomized controlled trial

BACKGROUND

According to the national census, China has gradually become an aging society; moreover, aging has become an irreversible worldwide trend in the twenty-first century. Aging can lead to decreased physical function, mobility, cardiopulmonary function and quality of life (QOL). The feasibility and benefits of core strength training (CST) and Tai Chi Chuan (TCC) in older adults (including improving cardiovascular, musculoskeletal, and mental health outcomes) have been confirmed in previous studies. To date, these exercise programmes have not been systematically compared, and the potential benefits of their combined use have not been tested. The primary objective of this study protocol is to evaluate the effects of CST compared to those of TCC on the function of the musculoskeletal system and the cardiopulmonary system in older adults.The second objective is to test the effectiveness of combined physical training that incorporates CST and TCC.

METHODS

A randomized, single-blind, parallel-controlled trial will be conducted. Three hundred eighty-four participants who meet the eligibility criteria will be randomly allocated into a control group, a CST group, a TCC group, and a combined group in a 1:1:1:1 ratio. Participants in the CST group and the TCC group will respectively receive CST and TCC training at a frequency of 1 hour per day, 5 days per week, totally 12 weeks. Participants in the combined group will receive 30 minutes CST and 30 minutes TCC training per day, 5 days per week, totally 12 weeks. No specific exercises will be required of the participants in the control group. Both musculoskeletal and cardiopulmonary function outcomes, including bone density detection, balance and coordination ability, walking ability, pain visual analogue scale (VAS) score, fall risk assessment, activities of daily living, pulmonary function tests, color sonography and electrocardiogram, will be evaluated by blinded operators at baseline, 13 weeks and 25 weeks (follow-up period).

DISCUSSION

The results of this study protocol are expected to clarify the synergistic effect of CST and TCC training on musculoskeletal and cardiopulmonary function in older adults. Furthermore, these findings will confirm whether combined or exclusive CST and TCC training, is more effective at improving functional outcomes in the elderly.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR-IOR-17010769. Registration date: March 3, 2017.

Field Test Performance of Junior Competitive Surf Athletes following a Core Strength Training Program

Lower body and core muscular strength are essential for optimal performance in many sports and competitive surfers have similar strength demands when maneuvering a surfboard to achieve competition success. Presently, the use of unstable surfaces is excessively utilized by surf coaches and trainers and to date, research does not support this as an effective training method for long-term improvements. Therefore, the purpose of this study was to determine the effectiveness of an 8-week Core Strength Training Program (CSTP) on a battery of field tests specific to assessing core musculature and lower body strength for junior competitive surf athletes. Nineteen American junior competitive surf athletes (age:15.7±1.01yrs, height:1.77±0.007m, mass:64.67±9.08kg) completed pre- and post-tests with a transitional pre-season to in-season 8-week CSTP intervention. The battery of tests included: rotational power (RP), time to peak acceleration (TP), maximal acceleration (Ma), maximal countermovement jump (CMJ), estimated peak power (PP), core strength (CS), core endurance (CE), and rotational flexibility (RF). Means, standard deviations, RMANOVA with a significance level of p < 0.05, and effect sizes were computed. Results demonstrated significant improvements in L.RP, TP, CMJ, PP, CS, and RF. Based on the results, the CSTP is an effective training program for surf coaches and strength and conditioning professionals to improve strength in the core musculature and lower body. In addition, we conclude implementation of the CSTP enhances athletic performance measurements which will likely increase competition success.

Sport-Specific Assessment of the Effectiveness of Neuromuscular Training in Young Athletes

Neuromuscular training in young athletes improves performance and decreases the risk of injuries during sports activities. These effects are primarily ascribed to the enhancement of muscle strength and power but also balance, speed and agility. However, most studies have failed to demonstrate significant improvement in these abilities. This is probably due to the fact that traditional tests do not reflect training methods (e.g., plyometric training vs. isometric or isokinetic strength testing, dynamic balance training vs. static balance testing). The protocols utilized in laboratories only partially fulfill the current needs for testing under sport-specific conditions. Moreover, laboratory testing usually requires skilled staff and a well equipped and costly infrastructure. Nevertheless, experience demonstrates that high-technology and expensive testing is not the only way to proceed. A number of physical fitness field tests are available today. However, the low reliability and limited number of parameters retrieved from simple equipment used also limit their application in competitive sports. Thus, there is a need to develop and validate a functional assessment platform based on portable computerized systems. Variables obtained should be directly linked to specific features of particular sports and capture their complexity. This is essential for revealing weak and strong components of athlete performance and design of individually-tailored exercise programs. Therefore, identifying the drawbacks associated with the assessment of athlete performance under sport-specific conditions would provide a basis for the formation of an innovative approach to their long-term systematic testing. This study aims (i) to review the testing methods used for the evaluation of the effect of neuromuscular training on sport-specific performance in young athletes, (ii) to introduce stages within the Sport Longlife Diagnostic Model, and (iii) to propose future research in this topic. Analysis of the literature identified gaps in the current standard testing methods in terms of their low sensitivity in discriminating between athletes of varied ages and performance levels, insufficent tailoring to athlete performance level and individual needs, a lack of specificity to the requirements of particular sports and also in revealing the effect of training. In order to partly fill in these gaps, the Sport Longlife Diagnostic Model was proposed.

The Influence of Fatigued Core Muscles on Head Acceleration during Headers in Soccer

The core muscles play a central role in stabilizing the head during headers in soccer. The objective of this study was to examine the influence of a fatigued core musculature on the acceleration of the head during jump headers and run headers. Acceleration of the head was measured in a pre-post-design in 68 soccer players (age: 21.5 ± 3.8 years, height: 180.0 ± 13.9 cm, weight: 76.9 ± 8.1 kg). Data were recorded by means of a telemetric 3D acceleration sensor and with a pendulum header. The treatment encompassed two exercises each for the ventral, lateral, and dorsal muscle chains. The acceleration of the head between pre- and post-test was reduced by 0.3 G (p = 0.011) in jump headers and by 0.2 G (p = 0.067) in run headers. An additional analysis of all pretests showed an increased acceleration in run headers when compared to stand headers (p < 0.001) and jump headers (p < 0.001). No differences were found in the sub-group comparisons: semi-professional vs. recreational players, offensive vs. defensive players. Based on the results, we conclude that the acceleration of the head after fatiguing the core muscles does not increase, which stands in contrast to postulated expectations. More tests with accelerated soccer balls are required for a conclusive statement.

Effectiveness of Traditional Strength vs. Power Training on Muscle Strength, Power and Speed with Youth: A Systematic Review and Meta-Analysis

Numerous national associations and multiple reviews have documented the safety and efficacy of strength training for children and adolescents. The literature highlights the significant training-induced increases in strength associated with youth strength training. However, the effectiveness of youth strength training programs to improve power measures is not as clear. This discrepancy may be related to training and testing specificity. Most prior youth strength training programs emphasized lower intensity resistance with relatively slow movements. Since power activities typically involve higher intensity, explosive-like contractions with higher angular velocities (e.g., plyometrics), there is a conflict between the training medium and testing measures. This meta-analysis compared strength (e.g., training with resistance or body mass) and power training programs (e.g., plyometric training) on proxies of muscle strength, power, and speed. A systematic literature search using a Boolean Search Strategy was conducted in the electronic databases PubMed, SPORT Discus, Web of Science, and Google Scholar and revealed 652 hits. After perusal of title, abstract, and full text, 107 studies were eligible for inclusion in this systematic review and meta-analysis. The meta-analysis showed small to moderate magnitude changes for training specificity with jump measures. In other words, power training was more effective than strength training for improving youth jump height. For sprint measures, strength training was more effective than power training with youth. Furthermore, strength training exhibited consistently large magnitude changes to lower body strength measures, which contrasted with the generally trivial, small and moderate magnitude training improvements of power training upon lower body strength, sprint and jump measures, respectively. Maturity related inadequacies in eccentric strength and balance might influence the lack of training specificity with the unilateral landings and propulsions associated with sprinting. Based on this meta-analysis, strength training should be incorporated prior to power training in order to establish an adequate foundation of strength for power training activities.