Influence of dynamic versus static core exercises on performance in field based fitness tests

Exploring the relationship between core stability and vertical jump in recreationally active male college students based on a suite of novel core stability assessments

Various assessments have contributed to inconsistent findings regarding the correlation between core stability and vertical jumps. Therefore, this study aimed to re-examine this correlation based on novel core stability assessments. Twenty-one recreationally active male college students (age, 21.7 ± 2.1 years; stature, 174.9 ± 6.7 cm; body mass, 67.7 ± 7.8 kg; leg length, 88.9 ± 4.8 cm; arm length, 87.8 ± 4.0 cm) participated in this experiment. Core stability was divided into static and dynamic core stabilities, with the static core stability measured using the Eight-Level Prone Bridge and Five-Level Side Bridge tests and the dynamic core stability measured using the Y Balance Test (YBT). These tests comprehensively evaluate core stability as it is defined. Kinematic and kinetic data on vertical jumps were collected to provide process information beyond the outcome performance. Subsequently, these data were correlated with core stability for a deeper insight into the relationship between core stability and the process and outcome performance of vertical jumps. The main results revealed that the Eight-Level Prone Bridge demonstrated moderate to substantial correlations with Δ F y ‾ , Δ I y , Δ D l e f t k n e e z , and Δ D l e f t a n k l e y (-0.62 ≤ r ≤ 0.52); the Five-Level Side Bridge exhibited moderate correlations with Δ F x ‾ , Δ F y ‾ , Δ I x , Δ I y , Δ D l e f t k n e e z , and Δ D l e f t a n k l e y (-0.52 ≤ r ≤ 0.59); YBT displayed moderate correlations with F z ‾ , F l e f t z ‾ , Δ D l e f t a n k l e y , Δ D r i g h t a n k l e y , Δ D l e f t a n k l e z , Δ D r i g h t a n k l e z , NΔ T a n k l e y ‾ , and N T l e f t a n k l e z ‾ (-0.54 ≤ r ≤ 0.54) during the propulsive phase of vertical jumps. However, no significant correlations were observed between static/dynamic core stability and jumping height. Therefore, individuals with greater core stability should experience improved process performance (better movement quality), although this benefit is ineffective in translating into jumping height improvement due to impaired explosive features. Coaches may consider core stability in training to trigger an improved process performance of the vertical jump when the technique is the key issue to be solved, although future studies are required to verify this further.

Effect of core training on skill-related physical fitness performance among soccer players: A systematic review

Aims

This study aims to present an in-depth review of the available literature on the effect of core training on skill-related physical fitness performance among soccer players, as well as to offer suggestions for researchers and coaches.

Methods

The data in this study were presented based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Using scientific databases and web search engines including Scopus, Ebscohost, Web of Science, PubMed, and Google Scholar, researchers collected studies from the published literature. Only 26 of the 84 articles satisfied all the inclusion criteria and were thus included in the systematic review. The quality of each study was determined using the PEDro scale. The scores for 26 studies range between three and six.

Results

Core training can improve soccer players' skill-related physical fitness, including their power, speed, balance, and agility.

Conclusion

The core is the anatomic and functional center of the body as well as its "engine." All movements emanate from the center of the body and are transmitted to the extremities. The core muscles differ from the limb muscles because they frequently cocontract, thus making the torso hard to the point whereby all the muscles work together to become synergists. Theoretically, a strong core permits the passage of force from the lower body to the upper body with minimal energy loss in the torso. Based on the 26 studies, this review suggests that core training should be incorporated into the daily training sessions of soccer players, with a minimum frequency and length of 15 min per training session, twice per week, for 4 weeks.

Systematic review registration

https://inplasy.com, identifier INPLASY202290045.

Observational Screening Guidelines and Smartphone Accelerometer Thresholds to Establish the Intensity of Some of the Most Popular Core Stability Exercises

The lack of training load control, mainly exercise intensity, is one of the main limitations of core stability (CS) programs, which makes the training individualization and the analysis of the dose-response relationship difficult. The objectives of this study were to assess the inter-and intra-rater agreement when using new observational screening guidelines to decide if a core stability exercise represents an adequate training intensity level for a given participant. Besides, the relationship between experts' ratings based on these criteria and pelvic accelerations recorded with a smartphone accelerometer was also analyzed. Ten healthy physically active participants with a smartphone accelerometer placed on their pelvis were video-taped while performing a progression of seven variations of the front bridge, back bridge, side bridge and bird-dog exercises. Two expert and four non-expert raters watched the videos and used the observational screening guidelines to decide for each exercise variation if it represented an adequate training intensity level or not. In order to analyze the inter-and intra-rater agreement, several Kappa (κ) statistics were used. Receiver operating characteristic (ROC) curves to explore if the accelerometry allowed to establish pelvic acceleration thresholds representing the minimum level of exercise intensity for CS training. Cut-off acceleration values were calculated balancing sensitivity (Se) and 1-specifity (1-Sp) indexes (i.e., Youden index) or minimizing 1-Sp. The intra-and inter-rater analysis showed a substantial-high level of agreement with a prevalence-adjusted bias-adjusted Kappa > 0.69. The ROC curves showed that the acceleration thresholds for the bridging exercises were very similar, with global cut-off values of 0.35 m/s² (Se = 82%; 1-Sp = 15%) when using the Youden Index and of 0.50 m/s² when minimizing 1-Sp (Se = 31%), whilst the bird-dog exercise showed lower cut-off values (Youden Index: 0.21 m/s², Se = 90%, 1-Sp = 16%; minimizing 1-Sp: 0.32 m/s², Se = 40%). Overall, this study provides observational screening guidelines and smartphone accelerometer thresholds to facilitate the decision-making process when setting the intensity of some of the most popular core stability exercises in young physically active individuals.

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.

Progressions of core stabilization exercises based on postural control challenge assessment

PURPOSE

The intensity progression of core stabilization exercises (CSEs) is usually based on personal criteria rather than on objective parameters. To develop exercise progressions for four of the most common CSEs based on the postural control challenge imposed on the participants, and to analyze the effect of participants' sex and postural control level on these progressions.

METHODS

Seventy-six males and females performed five variations of front bridge, back bridge, side bridge and bird-dog exercises on two force platforms. The mean velocity of the center of pressure displacement was calculated to assess exercise intensity through the measurement of the participants' body sway (PBS).

RESULTS

In general, long bridges produced higher PBS than short bridges, bridging with single leg support produced higher PBS than bridging with double leg support and bridging on a hemisphere ball produced higher PBS than bridging on the floor. The most difficult bridging variations were those performed on a hemisphere ball with single leg support. Regarding the bird-dog, two-point positions produced higher PBS than three-point positions and the positions performed on a hemisphere ball produced higher PBS than those performed on the floor.

CONCLUSION

The CSE progressions obtained by males and females were very similar. However, the participants with high trunk control showed less significant differences between exercise variations than the participants with low trunk control, which shows the need to individualize the progressions according to the participants' training level. Overall, this study provides useful information to guide the prescription of CSE progressions in young physically active individuals.

Association Between Motor Skills and Musculoskeletal Physical Fitness Among Preschoolers

OBJECTIVE

Previous work is conflicted regarding the relationship between motor skill development and physical activity. One potential explanation for this equivocality is the difficulty and lack of precision in physical activity measurement, particularly within preschool populations. Our exploration of plank performance as a proxy measure for fitness addresses a void in the literature, as few studies have investigated the role of motor skill development on fitness. The purpose of this study was to evaluate the potential relationship between motor skill level and musculoskeletal endurance (via the plank test).

METHODS

Data from the 2012 National Youth Fitness Survey were used, which included 224 preschool-aged children (3-5 years). Motor skill level was assessed from the Test of Gross Motor Development-Second Edition (TGMD2). Motor skill parameters included general motor skills, locomotor skills, and object control skills.

RESULTS

Within this nationally representative sample of preschoolers, increased motor skills were positively associated with plank performance [General Motor Skills (β = 0.45; 95% CI 0.31-0.59), locomotor skills (β = 1.88; 95% CI 1.15-2.61), and object control skills (β = 2.05; 95% CI 1.11-2.98)].

CONCLUSION

Motor skill level in this national preschool sample was associated with musculoskeletal endurance. Thus, future interventions should aim to develop and refine motor skills among preschoolers.

Training intensity quantification of core stability exercises based on a smartphone accelerometer

Although core stability (CS) training is largely used to enhance motor performance and prevent musculoskeletal injuries, the lack of methods to quantify CS training intensity hinders the design of CS programs and the comparison and generalization of their effects. The aim of this study was to analyze the reliability of accelerometers integrated into smartphones to quantify the intensity of several CS isometric exercises. Additionally, this study analyzed to what extent the pelvic acceleration data represent the local stability of the core structures or the whole-body postural control. Twenty-three male and female physically-active individuals performed two testing-sessions spaced one week apart, each consisting of two 6-second trials of five variations of frontal bridge, back bridge, lateral bridge and bird-dog exercises. In order to assess load intensity based on the postural control challenge of CS exercises, a smartphone accelerometer and two force platforms were used to measure the mean pelvic linear acceleration and the mean velocity of the centre of pressure displacement, respectively. Reliability was assessed through the intra-class correlation coefficient (ICC_3,1) and the standard error of measurement (SEM). In addition, Pearson coefficient was used to analyze the correlation between parameters. The reliability analysis showed that most CS exercise variations obtained moderate-to-high reliability scores for pelvic acceleration (0.71<ICC<0.88; 13.23%≤SEM≤22.99%) and low-to-moderate reliability scores for centre of pressure displacement (0.24<ICC<0.89; 9.88%≤SEM≤35.90%). Regarding the correlation analysis, correlations between pelvic acceleration and centre of pressure displacement were moderate-to-high (0.52≤r≤0.81). Based on these results, smartphone accelerometers seem reliable devices to quantify isometric CS exercise intensity, which is useful to identify the individuals’ CS status and to improve the dose-response characterization of CS programs.

Effects of ten weeks dynamic or isometric core training on climbing performance among highly trained climbers

This is the first study to compare the effects of isometric vs. dynamic core training and characterize core-training adaptations using climbing-specific performance and core strength tests in elite climbers. The aim of the study was to compare the effects of attending a progressive core-training program on climbing performance. 19 advanced and elite climbers (7.3±5.6 years climbing experience, red point skill grade 19 IRCRA) were randomized into a dynamic (DCT) or isometric (ICT) core training group and trained twice weekly for ten weeks. The climbers were tested using two climbing-specific core tests (body lock-off and body-lift) and four non-specific core strength tests-one dynamic (superman) and three isometric (trunk flexion and trunk rotation left and right). Between group comparisons showed no differences between the groups at post-test (p = 0.328-0.824) and neither group demonstrated greater improvement compared with the other (p = 0.300-0.926). The ICT group demonstrated 10.8% and 29.6% improvement in trunk flexion and body-lift (p = 0.029-0.037 with no improvement in body lock-off and rotation (p = 0.101-0.343). The DCT group demonstrated 5.0-14.9% improvement in the core strength tests (p = 0.012-0.043), a non-significant 33.8% improvement in body-lift (p = 0.100) and no improvement in body lock-off (p = 0.943). In conclusion, none of the training groups demonstrated greater improvement than the other and both dynamic and isometric core training improved climbing-specific test performance. Dynamic training was slightly more favorable although not significantly superior to isometric core training in improving core strength.

Safety and efficacy of exercise training in adults with Pompe disease: evalution of endurance, muscle strength and core stability before and after a 12 week training program

BACKGROUND

Pompe disease is a proximal myopathy. We investigated whether exercise training is a safe and useful adjuvant therapy for adult Pompe patients, receiving enzyme replacement therapy.

METHODS

Training comprised 36 sessions of standardized aerobic, resistance and core stability exercises over 12 weeks. Before and after, the primary outcome measures safety, endurance (aerobic exercise capacity and distance walked on the 6 min walk test) and muscle strength, and secondary outcome measures core stability, muscle function and body composition, were evaluated.

RESULTS

Of 25 patients enrolled, 23 successfully completed the training. Improvements in endurance were shown by increases in maximum workload capacity (110 W before to 122 W after training, [95 % CI of the difference 6 · 0 to 19 · 7]), maximal oxygen uptake capacity (69 · 4 % and 75 · 9 % of normal, [2 · 5 to 10 · 4]), and maximum walking distance (6 min walk test: 492 meters and 508, [-4 · 4 to 27 · 7] ). There were increases in muscle strength of the hip flexors (156 · 4 N to 180 · 7 N [1 · 6 to 13 · 6) and shoulder abductors (143 · 1 N to 150 · 7 N [13 · 2 to 35 · 2]). As an important finding in secondary outcome measures the number of patients who were able to perform the core stability exercises rose, as did the core stability balancing time (p < 0.05, for all four exercises). Functional tests showed small reductions in the time needed to climb four steps (2 · 4 sec to 2 · 1, [- 0 · 54 to -0 · 04 ]) and rise to standing position (5 · 8 sec to 4 · 8, [-2 · 0 to 0 · 0]), while time to run, the quick motor function test results and body composition remained unchanged.

CONCLUSIONS

Our study shows that a combination of aerobic, strength and core stability exercises is feasible, safe and beneficial to adults with Pompe disease.

Sport-Specific Training Targeting the Proximal Segments and Throwing Velocity in Collegiate Throwing Athletes

CONTEXT

The ability to generate, absorb, and transmit forces through the proximal segments of the pelvis, spine, and trunk has been proposed to influence sport performance, yet traditional training techniques targeting the proximal segments have had limited success improving sport-specific performance.

OBJECTIVE

To investigate the effects of a traditional endurance-training program and a sport-specific power-training program targeting the muscles that support the proximal segments and throwing velocity.

DESIGN

Randomized controlled clinical trial.

SETTING

University research laboratory and gymnasium.

PATIENTS OR OTHER PARTICIPANTS

A total of 46 (age = 20 ± 1.3 years, height = 175.7 ± 8.7 cm) healthy National Collegiate Athletic Association Division III female softball (n = 17) and male baseball (n = 29) players.

INTERVENTION(S)

Blocked stratification for sex and position was used to randomly assign participants to 1 of 2 training groups for 7 weeks: a traditional endurance-training group (ET group; n = 21) or a power-stability-training group (PS group; n = 25). Mean Outcome Measure(s) : The change score in peak throwing velocity (km/h) normalized for body weight (BW; kilograms) and change score in tests that challenge the muscles of the proximal segments normalized for BW (kilograms). We used 2-tailed independent-samples t tests to compare differences between the change scores.

RESULTS

The peak throwing velocity (ET group = 0.01 ± 0.1 km/h/kg of BW, PS group = 0.08 ± 0.03 km/h/kg of BW; P < .001) and muscle power outputs for the chop (ET group = 0.22 ± 0.91 W/kg of BW, PS group = 1.3 ± 0.91 W/kg of BW; P < .001) and lift (ET group = 0.59 ± 0.67 W/kg of BW, PS group = 1.4 ± 0.87 W/kg of BW; P < .001) tests were higher at postintervention in the PT than in the ET group.

CONCLUSIONS

An improvement in throwing velocity occurred simultaneously with measures of muscular endurance and power after a sport-specific training regimen targeting the proximal segments.

Six weeks of core stability training improves landing kinetics among female capoeira athletes: a pilot study

Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6 (p=0.528, p=0.261, and p=0.877, respectively). This study provides evidence that trunk dominant core stability training improves landing kinetics without improving jump height, and may reduce lower extremity injury risk in female athletes.

An electromyographic comparison of a modified version of the plank with a long lever and posterior tilt versus the traditional plank exercise

The purpose of the study was to compare core muscle activation of the tradition prone plank with a modified version performed with a long-lever and posterior-tilt using surface electromyography. To further determine if a specific component of this modified plank was more effective than the other in enhancing muscle activity, the plank with a long lever and the plank with a posterior pelvic tilt were studied individually. Nineteen participants performed all four variations of the plank for 30 seconds in a randomized order with 5-minute rest between exercise bouts. Compared to the traditional prone plank, the long-lever posterior-tilt plank displayed a significantly increased activation of the upper rectus abdominis (p < 0.001), lower abdominal stabilizers (p < 0.001), and external oblique (p < 0.001). The long-lever plank showed significantly greater activity compared to the traditional plank in the upper rectus abdominis (p = 0.015) and lower abdominal stabilizers (p < 0.001), while the posterior tilt plank elicited greater activity in the external oblique (p = 0.028). In conclusion, the long-lever posterior-tilt plank significantly increases muscle activation compared to the traditional prone plank. The long-lever component tends to contribute more to these differences than the posterior-tilt component.