The effects of traditional, superset, and tri-set resistance training structures on perceived intensity and physiological responses

Impact of squat set configuration on mechanical performance in paired sets of upper-body exercises

BACKGROUND

Paired sets and alternative set configurations (e.g., cluster sets) are frequently employed by strength and conditioning practitioners; however, their synergistic impact remains underexplored in research. This study aimed to elucidate whether the set configuration used in a lower-body exercise affects mechanical performance during paired sets of upper-body exercises.

METHODS

Twenty-one resistance-trained individuals (14 men and 7 women) randomly completed three experimental sessions that involved four sets of five repetitions at 75%1RM during both the bench press and bench pull exercises. The three experimental sessions varied solely in the activity conducted during the inter-set rest periods of each upper-body exercise: (i) Traditional squat - six squat repetitions without intra-set rest at 65%1RM; (ii) Rest redistribution squat - two clusters of three repetitions of the squat exercise at 65%1RM with 30 s of intra-set rest; and (iii) Passive rest - no exercise.

RESULTS

The rest redistribution set configuration allowed the sets of the squat exercise to be performed at a faster velocity than the traditional set configuration (p = 0.037). However, none of the mechanical variables differed between the exercise protocols neither in the bench press (p ranged from 0.279 to 0.875) nor in the bench pull (p ranged from 0.166 to 0.478).

CONCLUSIONS

Although rest redistribution is an effective strategy to alleviate fatigue during the sets in which it is implemented, it does not allow subjects to perform better in subsequent sets of the training session.

Combined Effects of Listening to Preferred Music and Video Feedback, during Warm-Up, on Physical Performance in Young Kickboxers

Although studies have indicated that the prior use of video feedback and music listening separately improves physical performance and positive feelings in various sports, to our knowledge, no studies have investigated their combined effect in combat-sports-specific tasks. The aim of this study was to determine the combined effect of listening to preferred music and video feedback on aerobic and anaerobic performance in male kickboxers. In a counterbalanced crossover study design, twenty kickboxers underwent three kicking exercises under one of three conditions: (1) control condition, (2) combined listening to preferred music and video feedback, and (3) video feedback during 10-min of rope warm-up. Kickboxers performed a ten-second kicking test, multiple ten-second kick test, and progressive taekwondo test. The total number of kicks, fatigue index, heart rate, rate of perceived exertion, and feeling scale were measured. The combined music and video feedback condition improved the number of kicks with a better positive feeling scale (F ≥ 7.4, p ≤ 0.002, ηp2 ≥ 0.28) than the video feedback and control conditions in all three kicking exercises, while the video feedback alone led to better kick performances and a better feeling scale than the control condition in the ten-second and multiple ten-second kicking tests (p ≤ 0.016). The combined listening to preferred music and video feedback condition was more effective at enhancing the positive feeling scale and repeated roundhouse kick performance. Future investigations should examine the application of video feedback and listening to music in various kickboxing tasks including punches and kicks.

The Effects and Reproducibility of 10, 20, and 30% Velocity Loss Thresholds on Acute and Short-Term Fatigue and Recovery Responses

ABSTRACT

Weakley, J, Johnston, RD, Cowley, N, Wood, T, Ramirez-Lopez, C, McMahon, E, and García-Ramos, A. The effects and reproducibility of 10, 20, and 30% velocity loss thresholds on acute and short-term fatigue and recovery responses. J Strength Cond Res 38(3): 465-473, 2024-This study aimed to establish the effects and reproducibility of implementing 10, 20, and 30% velocity loss thresholds (VLTs) during the free-weight barbell back squat on acute and short-term perceived soreness, neuromuscular fatigue, and physical performance. Using a repeated, counterbalanced, crossover design, 12 team-sport athletes completed on separate sessions 5 sets of the free-weight barbell back-squat until reaching VLTs of either 10, 20, or 30%. Outcomes were measured immediately postexercise and 24 hours after each session. To assess reproducibility, the same sessions were repeated after 4 weeks. Immediately postexercise, small differences in countermovement jump (CMJ) and 10-m sprint performance were observed between VLT conditions, whereas small to moderate differences in differential ratings of perceived exertion were reported (10% < 20% < 30%). At 24 hours, trivial differences in CMJ outcomes were found but small differences in 10-m sprint performance were detected between conditions (10% < 20% < 30%). In addition, at 24 hours, a single small difference in radial deformation using tensiomyography was found between 10 and 30% conditions, whereas large to very large differences in perceived soreness were reported between conditions (10% < 20% < 30%). Finally, the standard error of measurement of all outcome measures at 24 hours were of a similar magnitude to those reported in tightly controlled, short-term studies. Collectively, these findings demonstrate that VLTs help control the fatigue outcomes that occur as a response to resistance training and that they are reproducible. Therefore, for practitioners who wish to prescribe resistance training and be confident in the subsequent fatigue response, it is strongly advised that VLTs are implemented.

Impact of active intra-complex rest intervals on post-back squat versus hip thrust jumping potentiation

This study investigated the impact of active rest intervals within a lower body complex training session on post-activation performance enhancement (PAPE) response in amateur soccer players. Twelve soccer players took part in four different experimental conditions. These sessions included 2 sets of lower body complex-paired exercises, each involving 3 repetitions of either back squats or hip thrusts at 90% one-repetition maximum (1RM) as a conditioning activity paired with a broad jump and countermovement jump. Between those exercises in active intra-complex rest interval conditions, participants were performing 8 repetitions of bench press at 75%1RM or, in passive intra-complex rest interval conditions, rested while seated. A significant main effect of a set to increase broad jump length (p = 0.002), countermovement jump height (p = 0.002), and modified reactive strength index (p = 0.005) was revealed, without any significant differences between conditions. Post-hoc comparisons showed a significant increase in broad jump length from baseline to Set-2 (231 ± 13 vs. 234 ± 13 cm; p = 0.003; ES = 0.22). On the other hand, countermovement jump height and modified reactive strength index significantly increased from baseline to Set-1 (34.4 ± 3.6 vs. 35.6 ± 3.9 cm; p = 0.027; ES = 0.31 and 0.4 ± 0.05 vs. 0.45 ± 0.09; p = 0.005; ES = 0.66). Results of this study showed that to sustain a high training density, sports practitioners may incorporate upper body exercises within the intra-complex rest interval during lower limb complex training sessions and still elicit a significant PAPE effect.

Upper-lower body super-sets vs. traditional sets for inducing chronic athletic performance improvements

Background

To promote chronic adaptations, resistance training needs the manipulation of different variables, among them, the order of the exercises and sets. Specifically, for velocity-based training, paired exercises alternating upper and/or lower-body muscle groups appear to be a good choice to promote neuromuscular adaptations.

Objective

This study aimed to compare the effect of two velocity-based training programs only differing in the set configuration on muscle strength, muscular endurance and jump performance.

Methods

Moderately strength-trained men were allocated into a traditional (TS, n= 8) or alternating sets (AS, n= 9) configuration group to perform a 6-week velocity-based training program using the full squat (SQ) and bench press (BP) exercises. The TS group completed all sets of the full squat (SQ) exercise before performing the bench press (BP) sets, whereas the AS group completed the first set of each exercise in an alternating manner. Training frequency, relative load, number of sets, percentage of velocity loss (%VL) within the set and inter-set rest were matched for both groups. Countermovement jump height (CMJ), load (kg)-velocity relationship, predicted 1RM, and muscular endurance for each exercise were evaluated at pre- and post-training.

Results

The TS and AS groups obtained similar and non-significant improvements in CMJ (3.01 ± 4.84% and 3.77 ± 6.12%, respectively). Both groups exhibited significant and similar increases in muscle strength variables in SQ (6.19-11.55% vs. 6.90-011.76%; p = 0.033-0.044, for TS and AS, respectively), BP (6.19-13.87% and 3.99-9.58%; p = 0.036-0.049, for TS and AS group, respectively), and muscular endurance in BP (7.29 ± 7.76% and 7.72 ± 9.73%; p = 0.033, for the TS and AS group, respectively). However, the AS group showed a greater improvement in muscular endurance in SQ than the TS group (10.19 ± 15.23% vs. 2.76 ± 7.39%; p = 0.047, respectively). Total training time per session was significantly shorter (p = 0.000) for AS compared to TS group.

Conclusions

Training programs performing AS between SQ and BP exercises with moderate loads and %VL induce similar jump and strength improvements, but in a more time-efficient manner, than the traditional approach.

The Acute and Chronic Effects of Implementing Velocity Loss Thresholds During Resistance Training: A Systematic Review, Meta-Analysis, and Critical Evaluation of the Literature

BACKGROUND

Velocity loss (VL) experienced in a set during resistance training is often monitored to control training volume and quantify acute fatigue responses. Accordingly, various VL thresholds are used to prescribe resistance training and target different training adaptations. However, there are inconsistencies in the current body of evidence regarding the magnitude of the acute and chronic responses to the amount of VL experienced during resistance training.

OBJECTIVE

The aim of this systematic review was to (1) evaluate the acute training volume, neuromuscular, metabolic, and perceptual responses to the amount of VL experienced during resistance training; (2) synthesize the available evidence on the chronic effects of different VL thresholds on training adaptations; and (3) provide an overview of the factors that might differentially influence the magnitude of specific acute and chronic responses to VL during resistance training.

METHODS

This review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five databases were searched, and studies were included if they were written in English, prescribed resistance training using VL, and evaluated at least one (1) acute training volume, neuromuscular, metabolic, or perceptual response or (2) training adaptation. Risk of bias was assessed using a modified Cochrane Collaboration's tool for assessing the risk of bias in randomized trials. Multilevel and multivariate meta-regressions were performed where possible.

RESULTS

Eighteen acute and 19 longitudinal studies met the inclusion criteria, of which only one had more than one risk of bias item assessed as high risk. Based on the included acute studies, it seems that the number of repetitions per set, blood lactate concentration, and rating of perceived exertion generally increase, while countermovement jump height, running sprint times, and velocity against fixed loads generally decrease as VL increases. However, the magnitude of these effects seems to be influenced, among other factors, by the exercise and load used. Regarding training adaptations, VL experienced during resistance training did not influence muscle strength and endurance gains. Increases in VL were associated with increases in hypertrophy (b = 0.006; 95% confidence interval [CI] 0.001, 0.012), but negatively affected countermovement jump (b = - 0.040; 95% CI - 0.079, - 0.001), sprint (b = 0.001; 95% CI 0.001, 0.002), and velocity against submaximal load performance (b = - 0.018; 95% CI - 0.029, - 0.006).

CONCLUSIONS

A graded relationship exists between VL experienced during a set and acute training volume, neuromuscular, metabolic, and perceptual responses to resistance training. However, choice of exercise, load, and individual trainee characteristics (e.g., training history) seem to modulate these relationships. The choice of VL threshold does not seem to affect strength and muscle endurance gains whereas higher VL thresholds are superior for enhancing hypertrophy, and lower VL thresholds are superior for jumping, sprinting, and velocity against submaximal loads performance.

CLINICAL TRIAL REGISTRATION

The original protocol was prospectively registered ( https://osf.io/q4acs/ ) with the Open Science Framework.

Beyond Mechanical Tension: A Review of Resistance Exercise-Induced Lactate Responses & Muscle Hypertrophy

The present review aims to explore and discuss recent research relating to the lactate response to resistance training and the potential mechanisms by which lactate may contribute to skeletal muscle hypertrophy or help to prevent muscle atrophy. First, we will discuss foundational information pertaining to lactate including metabolism, measurement, shuttling, and potential (although seemingly elusive) mechanisms for hypertrophy. We will then provide a brief analysis of resistance training protocols and the associated lactate response. Lastly, we will discuss potential shortcomings, resistance training considerations, and future research directions regarding lactate's role as a potential anabolic agent for skeletal muscle hypertrophy.

Effects of one long vs. two short resistance training sessions on training volume and affective responses in resistance-trained women

The aim of this study was to compare the acute effects of performing a lower body resistance training program in one long or two shorter sessions in 1 day on training volume and affective measures. Employing a randomized-crossover design, 23 resistance-trained women (22 ± 2 years, 166 ± 6 cm, and 66.4 ± 7.5 kg) performed two training days consisting of (i) one long (46 min) or (ii) two short sessions (total of 43 min) separated by 3.5–5 h. Each training day was separated by 4-6 days and consisted of three sets to failure for six exercises. Training volume (number of repetitions lifted) were recorded during the sessions. Rating of perceived exertion for effort (RPE), rating of perceived exertion for discomfort (RPD), session displeasure/pleasure (sPDF) and exercise enjoyment (EES) were measured 10 min after each session. Participants also completed a readiness to train questionnaire (7 questions), 24 h after each session, and which training protocol they preferred, 48 h after the last session. The long session led to higher RPE (+1 point, p < 0.001, ES = 1.07), RPD (+1 point, p = 0.043, ES = 0.53) and sPDF (p = 0.010, ES = 0.59) compared to the short sessions. There was no difference in EES (p = 0.118, ES = 0.33). The short sessions had 3% higher training volume than the long session (p = 0.002, ES = 0.42). There were no differences in perceived readiness to train 24 h after the sessions (range: p = 0.166–0.856 and ES = 0.08–0.32). Twenty-two participants preferred the long session, while one preferred the short sessions. In conclusion, performing a longer, lower body, resistance training session led to greater perceptions of effort, discomfort and session pleasure than splitting the same program into two shorter sessions among resistance-trained women. However, two shorter sessions led to a greater training volume.

Post-Activation Performance Enhancement: Save Time With Active Intra-Complex Recovery Intervals

This study aimed to determine whether the intra-complex active recovery within the strength-power potentiating complex will impact the upper-body post-activation performance enhancement effect and how the magnitude of this effect will change across the upper-body complex training session. Thirteen resistance-trained males [the age, body mass, height, experience in resistance training, and one-repetition maximum (1RM) in bench press were 27 ± 4 years; 92.3 ± 15.4 kg; 182 ± 6 cm; 6.4 ± 2.4 years, and 118 ± 29 kg, respectively) participated in this study. Each participant completed a baseline bench press throw performance assessment at 30% 1RM. Next, five strength-power potentiating complexes consisting of a bench press at 80% 1RM were tested until the average barbell velocity decreased by 10% as a conditioning activity, and 6 min later, a re-test of bench press throw was carried out. During one experimental session during the rest interval inside the complex, they performed swiss ball leg curls, while between the complexes, a plank exercise (PAP-A) was performed. During the second experimental session, participants performed no exercises within the strength-power potentiating complexes and between them (PAP). Under control conditions, participants ran the same protocol (as the PAP condition) without the conditioning activity (CTRL). Friedman's test showed significant differences in peak (test = 90.634; p < 0.0001; Kendall's W = 0.410) and average (test = 74.172; p < 0.0001; Kendall's W = 0.336) barbell velocities during bench press throw. Pairwise comparisons indicated that the peak and average barbell velocities significantly increased in the fourth set [p = 0.022, effect size (ES) = 0.76 and p = 0.013, ES = 0.69, respectively], and the average barbell velocity was also increased in the second set (p = 0.018, ES = 0.77) in comparison to the baseline value during the PAP-A condition. Moreover, the peak barbell velocity was increased in the second (p = 0.008, ES = 0.72) and third (p = 0.019, ES = 0.76) sets compared to the baseline value during the PAP condition. This study showed that body-weight lower-body exercise as an intra-complex active recovery did not impair the upper-body post-activation performance enhancement effect across the complex training session.

Acute Effect of Upper-Lower Body Super-Set vs. Traditional-Set Configurations on Bar Execution Velocity and Volume

This study aimed to compare the effect on bar execution velocity and number of repetitions between two velocity-based resistance training protocols only differing in the set configuration of the full-squat (SQ) and bench-press (BP) exercises. Moderately strength-trained men were assigned to a traditional (TS, n = 9)- or an alternating-set (AS, n = 10) configuration group to perform four testing sessions against different relative loads (55−60−65−70% 1RM). Relative load, magnitude of intra-set velocity loss (%VL), number of sets, inter-set recovery time, and exercise order were matched for both groups in each session. Mean propulsive velocity of the first repetition (MPVfirst), average number of repetitions per set (NRS), total number of repetitions (TNR), and total training time per session (TT) were measured. No significant differences between training conditions were observed for any relative load in MPVfirst, NRS, and TNR in both exercises. The TS group completed a significantly higher number of repetitions (p < 0.05) at faster velocities (MPV > 0.9−1.1 m·s−1) in the SQ. In conclusion, training sessions performing AS between SQ and BP exercises with moderate relative loads and %VL result in similar bar execution velocity and volume, but in a more time-efficient manner, than the traditional approach.

A Comparison of Affective Responses Between Time Efficient and Traditional Resistance Training

The aim of the study was to compare the acute effects of traditional resistance training and superset training on training duration, training volume and different perceptive measures. Twenty-nine resistance-trained participants (27 ± 7 years, 173 ± 9 cm, and 70 ± 14 kg) performed a whole-body workout (i) traditionally and (ii) as supersets of exercises targeting different muscle groups, in a randomized-crossover design. Each session was separated by 4–7 days, and consisted of eight exercises and three sets to failure. Training duration and number of repetitions lifted were recorded during the sessions. Rate of perceived exertion for effort (RPE), rate of perceived exertion for discomfort (RPD), session displeasure/pleasure (sPDF), and exercise enjoyment (EES) were measured 15 min after each session. Forty-eight hours after the final session participants reported which session they preferred. The superset session led to significantly higher values for RPE (1.3 points, p < 0.001, ES = 0.96) and RPD (1.0 points, p = 0.008, ES = 0.47) and tended to be higher for sPDF, i.e., more pleasurable, (p = 0.059, ES = 0.25) compared to the traditional session. There was no difference in EES (p = 0.661, ES = 0.05). The traditional session led to significantly increased training volume (4.2%, p = 0.011, ES = 0.34) and lasted 23 min (66%, p < 0.001, ES = 7.78) longer than the superset session. Eighteen of the participants preferred the superset session, while 11 preferred the traditional session. In conclusion, performing a whole-body workout as a superset session was more time-efficient, but reduced the training volume and was perceived with greater exertion for effort and discomfort than a traditional workout.

Tri-Set Training System Induces a High Muscle Swelling with Short Time Commitment in Resistance-Trained Subjects: A Cross-Over Study

The purpose of the present study was to assess performance and morphological acute responses to the tri-set (TRI) resistance-training system. In a random order, 18 subjects (years: 30.0 ± 5.6; weight: 81.8 ± 13.4 kg; height: 173 ± 6.2 cm; RT experience: 4.6 ± 1.7 years) performed 3 exercises targeting the pectoralis major muscle in two different experimental conditions: traditional system (TRAD) and TRI. The TRAD protocol referred to the completion of a single exercise set followed by a rest period. For the TRI protocol, one set of each exercise was performed sequentially with a minimal rest interval afforded (< 10 seconds). Both protocols were performed in 3 sets of 10RM. Pectoralis major muscle swelling (PM_MS), volume load (VL), internal training load (ITL) and training efficiency (TE) were calculated and compared between both protocols. Despite the low VL (-19.3%; p < 0.001), larger values of PM_MS (104.7%; p < 0.001), ITL (24.3%; p < 0.001) and TE (56.0%; p < 0.001) were observed during TRI compared to TRAD condition. In conclusion, the adoption of a TRI training protocol may induce distinct performance and morphological acute responses compared to TRAD, suggesting that resistance-trained subjects may experience a higher muscle swelling and intensity of effort with short time commitment when performing TRI system.

No Time to Lift? Designing Time-Efficient Training Programs for Strength and Hypertrophy: A Narrative Review

Abstract

Lack of time is among the more commonly reported barriers for abstention from exercise programs. The aim of this review was to determine how strength training can be most effectively carried out in a time-efficient manner by critically evaluating research on acute training variables, advanced training techniques, and the need for warm-up and stretching. When programming strength training for optimum time-efficiency we recommend prioritizing bilateral, multi-joint exercises that include full dynamic movements (i.e. both eccentric and concentric muscle actions), and to perform a minimum of one leg pressing exercise (e.g. squats), one upper-body pulling exercise (e.g. pull-up) and one upper-body pushing exercise (e.g. bench press). Exercises can be performed with machines and/or free weights based on training goals, availability, and personal preferences. Weekly training volume is more important than training frequency and we recommend performing a minimum of 4 weekly sets per muscle group using a 6–15 RM loading range (15–40 repetitions can be used if training is performed to volitional failure). Advanced training techniques, such as supersets, drop sets and rest-pause training roughly halves training time compared to traditional training, while maintaining training volume. However, these methods are probably better at inducing hypertrophy than muscular strength, and more research is needed on longitudinal training effects. Finally, we advise restricting the warm-up to exercise-specific warm-ups, and only prioritize stretching if the goal of training is to increase flexibility. This review shows how acute training variables can be manipulated, and how specific training techniques can be used to optimize the training response: time ratio in regard to improvements in strength and hypertrophy.

Graphic Abstract

Jump Training in Rugby Union Players: Barbell or Hexagonal Bar?

ABSTRACT

Weakley, JJS, Till, K, Read, DB, Leduc, C, Roe, GAB, Phibbs, PJ, Darrall-Jones, J, and Jones, B. Jump training in rugby union players: barbell or hexagonal bar?. J Strength Cond Res 35(3): 754-761, 2021-The countermovement jump (CMJ) is an exercise that can develop athletic performance. Using the conventional barbell (BAR) and hexagonal barbell (HEX) while jumping, the intensity can be increased. However, the bar that provides greater adaptations is unknown. Therefore, this study aimed to assess changes in loaded and unloaded CMJ with either a BAR or HEX across a 4-week mesocycle in rugby union players. Twenty-nine subjects were strength-matched and randomized into 2 groups. Subjects completed 3 sets of CMJ at 20% of 1 repetition maximum back squat, 3 times per week for 4 weeks, using either a BAR or HEX. Subjects completed an unloaded CMJ on a force plate before and after, whereas the highest peak concentric velocity during the jump squat was recorded in the first and last training sessions using a linear position transducer. Magnitude-based inferences assessed meaningful changes within- and between-groups. Possibly greater improvements in unloaded CMJ were found in the HEX group in jump height (effect size ± 90% confidence intervals: 0.27 ± 0.27), relative peak (0.21 ± 0.23), and mean power (0.32 ± 0.36). In addition, likely to very likely greater improvements were observed in the HEX group in peak velocity (0.33 ± 0.27), relative mean power (0.53 ± 0.30), mean force (0.47 ± 0.27), and 100-ms impulse (0.60 ± 0.48). Similar raw changes in jump squat peak velocity occurred (0.20-0.25 m·s-1), despite the likely greater ES occurring with the BAR (0.32 ± 0.26). These results indicate that training with the HEX leads to superior unloaded CMJ adaptations. In addition, practitioners should use either the HEX or BAR when aiming to enhance loaded jump ability.

The Validity and Reliability of Commercially Available Resistance Training Monitoring Devices: A Systematic Review

Background

Monitoring resistance training has a range of unique difficulties due to differences in physical characteristics and capacity between athletes, and the indoor environment in which it often occurs. Traditionally, methods such as volume load have been used, but these have inherent flaws. In recent times, numerous portable and affordable devices have been made available that purport to accurately and reliably measure kinetic and kinematic outputs, potentially offering practitioners a means of measuring resistance training loads with confidence. However, a thorough and systematic review of the literature describing the reliability and validity of these devices has yet to be undertaken, which may lead to uncertainty from practitioners on the utility of these devices.

Objective

A systematic review of studies that investigate the validity and/or reliability of commercially available devices that quantify kinetic and kinematic outputs during resistance training.

Methods

Following PRISMA guidelines, a systematic search of SPORTDiscus, Web of Science, and Medline was performed; studies included were (1) original research investigations; (2) full-text articles written in English; (3) published in a peer-reviewed academic journal; and (4) assessed the validity and/or reliability of commercially available portable devices that quantify resistance training exercises.

Results

A total of 129 studies were retrieved, of which 47 were duplicates. The titles and abstracts of 82 studies were screened and the full text of 40 manuscripts were assessed. A total of 31 studies met the inclusion criteria. Additional 13 studies, identified via reference list assessment, were included. Therefore, a total of 44 studies were included in this review.

Conclusion

Most of the studies within this review did not utilise a gold-standard criterion measure when assessing validity. This has likely led to under or overreporting of error for certain devices. Furthermore, studies that have quantified intra-device reliability have often failed to distinguish between technological and biological variability which has likely altered the true precision of each device. However, it appears linear transducers which have greater accuracy and reliability compared to other forms of device. Future research should endeavour to utilise gold-standard criterion measures across a broader range of exercises (including weightlifting movements) and relative loads.

Electronic supplementary material

The online version of this article (10.1007/s40279-020-01382-w) contains supplementary material, which is available to authorized users.

Improving the Signal-To-Noise Ratio When Monitoring Countermovement Jump Performance

ABSTRACT

Kennedy, RA and Drake, D. Improving the signal-to-noise ratio when monitoring countermovement jump performance. J Strength Cond Res 35(1): 85-90, 2021-Countermovement jump (CMJ) performance has been routinely used to monitor neuromuscular status. However, the protocol used to establish the criterion score is not well documented. The purpose of this study was to examine how the protocol used would influence of the sensitivity of CMJ variables in rugby union players. Fifteen male (age: 19.7 ± 0.5 years) rugby union players performed 8 CMJs on 2 occasions, separated by 7 days. The between-session coefficient of variation (CV) was calculated using 2 techniques for treating multiple trials, the average, and the trial with the best jump height (JH), and then compared with the smallest worthwhile change (SWC). The signal-to-noise ratio was measured as the group mean change in a variable divided by the CV. Using the average value across multiple trials is superior to the best trial method, based on lower CVs for all variables. Only the average performance across 6 or more trials was classified as ideal (CV < 0.5 × SWC) for peak velocity (PV). In addition, the signal-to-noise ratio for peak concentric power (PCP), PV, and JH were classified as good, irrespective of the treatment method. Although increasing the number of trials can reduce the random error, it may be pragmatic to simply take the average from 2 to 3 trials, facilitating a CV < SWC for PV, PCP, and JH. Due to its simplicity, JH may be considered the principal variable to monitor neuromuscular fatigue.

Cardiovascular Acute Effects of Traditional vs. Paired Set Resistance Training in Patients With Liver Cirrhosis

Purpose: This study compared the acute effects of two different resistance training methods on heart rate variability, blood pressure, and rating of perceived exertion in patients with liver cirrhosis. Methods: Ten patients with Child-Pugh A (seven women and three men) participated in two experimental sessions, in random order: The traditional set condition consisted of three sets of six exercises performed in a sequential manner, while the paired set condition consisted of alternating sets between two exercises (three pairs of exercises). Ten repetitions were performed for each set with 70% of a 10 repetition maximum load and with 2 min rest between sets. Blood pressure and heart rate variability were assessed pre-workout and for 60 min post-workout. The rating of perceived exertion was assessed at the end of the third set for each exercise. Results: Significant alterations in heart rate variability were observed when considering the lowest value obtained during recovery, in which the SDNN was reduced in both the traditional set and paired set conditions, as well as the root mean square of standard deviation for the traditional set condition (p < .05). Additionally, for the paired set condition, there was a significant reduction in the HFnu band and a significant increase in the LFnu band (p < .05). Effect size showed reductions in diastolic and mean blood pressure until 30 min in a small magnitude for traditional sets. Conclusion: Similar cardiovascular responses were observed between methods eliciting normal physiological responses within safe limits for patients with liver cirrhosis.

Show Me, Tell Me, Encourage Me: The Effect of Different Forms of Feedback on Resistance Training Performance

Weakley, J, Wilson, K, Till, K, Banyard, H, Dyson, J, Phibbs, P, Read, D, and Jones, B. Show me, tell me, encourage me: The effect of different forms of feedback on resistance training performance. J Strength Cond Res 34(11): 3157-3163, 2020-When performing resistance training, verbal kinematic feedback and visual kinematic feedback are known to enhance performance. In addition, providing verbal encouragement can assist in the attenuation of fatigue. However, the effects of these forms of feedback have never been compared. Consequently, this study aimed to quantify the effects of verbal kinematic feedback and visual kinematic feedback, and verbal encouragement on barbell velocity during the back squat. Furthermore, changes in performance were related to individual-reported conscientiousness. Twelve semiprofessional rugby union players volunteered to participate in the study that consisted of the subjects completing a set of the barbell back squat across 4 conditions (i.e., no-feedback [control], verbal feedback of kinematic information [verbal], visual feedback of kinematic information [visual], and verbal encouragement [encouragement]). In addition, participants completed a questionnaire before the study to assess conscientiousness. Magnitude-based inferences were used to assess differences between conditions, whereas Spearman's rank correlation coefficient was used to assess relationships between conscientiousness and changes in barbell velocity. All 3 forms of feedback showed almost certain improvements in barbell velocity, while differences between interventions were likely to very likely trivial. Changes in barbell velocity showed small to large inverse relationships with conscientiousness. These findings suggest that practitioners should supply kinematic feedback (verbally or visually) or, when technology is not available, provide athletes with encouraging statements while resistance training. Verbal encouragement may be of greatest benefit for individuals who demonstrate low levels of conscientiousness. Given these findings, practitioners are advised to use either technology or verbal encouragement to manipulate acute training outcomes.

Velocity Loss Thresholds Reliably Control Kinetic and Kinematic Outputs during Free Weight Resistance Training

Exercise velocity and relative velocity loss thresholds (VLTs) are commonly used in velocity-based resistance training. This study aims to quantify the between-day reliability of 10%, 20%, and 30% VLTs on kinetic and kinematic outputs, changes in external load, and repetition characteristics in well-trained athletes. Using a repeated, counter-balanced crossover design, twelve semi-professional athletes completed five sets of the back squat with an external load corresponding to a mean concentric velocity of ~0.70 m·s^-1 and a VLT applied. The testing sessions were repeated after four weeks of unstructured training to assess the long-term reliability of each VLT. A coefficient of variation (CV) <10% was used to classify outputs as reliable. Kinetic and kinematic outputs and external load were largely reliable, with only peak power during sets 2-5 within the 10% VLT condition demonstrating a CV >10% (CV: 11.14-14.92%). Alternatively, the repetitions completed within each set showed large variation (CV: 18.92-67.49%). These findings demonstrate that by utilizing VLTs, kinetic and kinematic outputs can be prescribed and replicated across training mesocycles. Thus, for practitioners wishing to reliably control the kinetic and kinematic stimulus that is being applied to their athletes, it is advised that a velocity-based approach is used.

The Effectiveness of Frequency-Based Resistance Training Protocols on Muscular Performance and Hypertrophy in Trained Males: A Critically Appraised Topic

Clinical Scenario: Manipulation of exercise variables in resistance training (RT) is an important component in the development of muscular strength, power, and hypertrophy. Currently, most research centers on untrained or recreationally trained subjects. This critically appraised topic focuses on studies that center on the well-trained subject with regard to frequency of training. Clinical Question: In well-trained male subjects, is there an association between RT frequency and the development of muscular strength and hypertrophy? Summary of Key Findings: Four studies met the inclusion criteria and were included for analysis. All studies showed that lower-frequency training could elicit muscular strength and hypertrophy increases. One study suggested that a higher frequency compared with a lower frequency may provide a slight benefit to hypertrophic development. One study reported a greater level of delayed onset muscle soreness with lower frequency training. The 4 studies demonstrate support for the clinical question. Clinical Bottom Line: Current evidence suggests that lower-frequency RT produces equal to greater improvements on muscular strength and hypertrophy in comparison to higher-frequency RT when volume is equated. The evidence is particularly convincing when lower-frequency RT is associated with a total-body training protocol in well-trained male subjects. Strength of Recommendation: There is moderate-to-strong evidence to suggest that lower-frequency RT, when volume is equated, will produce equal to greater improvements on muscular strength and hypertrophy in comparison to higher-frequency RT.

The effects of straight and alternating sets on volume load, training efficiency, and metabolic response in grapplers

BACKGROUND

The importance of strength in Brazilian jiu-jitsu (BJJ) has inspired several recommendations of resistance training (RT) in BJJ athletes, yet little is known about their responses to different RT approaches. Thus, we aimed to investigate volume, efficiency, and fatigue responses in two popular RT protocols.

METHODS

In a randomized crossover design, 12 male BJJ athletes (mean age: 24.5±3.1 years; height: 175±5 cm; body mass: 77.1±12.9 kg; body fat: 14.3±5.7%; BMI: 24.8±3.0) completed two separate RT protocols consisting of the same exercises performed either as straight sets (TRAD) or alternating sets (AST) for three sets to failure with a previously established 10-repetition maximum (10RM) load. Maximal number of repetitions (MNR), training duration, volume load (VL), and training efficiency (TE = VL/time), rating of perceived exertion (RPE), and blood lactate concentration (LAC) were assessed in each protocol.

RESULTS

MNR decreased steadily from first to last sets for all exercises, with no difference between protocols (P>0.05), resulting in the same VL. The shorter duration of AST resulted in increased TE (P<0.001), which was accompanied by higher RPE (P<0.001) and LAC (P<0.05), as well as higher session perceived load (P<0.01).

CONCLUSIONS

Given the role of VL as a driver of RT adaptations, both approaches may be suitable for improvements in strength and hypertrophy. The distinct differences in duration and metabolic response should be considered when implementing RT alongside regular sport training.

Training Considerations for Optimising Endurance Development: An Alternate Concurrent Training Perspective

Whilst the "acute hypothesis" was originally coined to describe the detrimental effects of concurrent training on strength development, similar physiological processes may occur when endurance training adaptations are compromised. There is a growing body of research indicating that typical resistance exercises impair neuromuscular function and endurance performance during periods of resistance training-induced muscle damage. Furthermore, recent evidence suggests that the attenuating effects of resistance training-induced muscle damage on endurance performance are influenced by exercise intensity, exercise mode, exercise sequence, recovery and contraction velocity of resistance training. By understanding the influence that training variables have on the level of resistance training-induced muscle damage and its subsequent attenuating effects on endurance performance, concurrent training programs could be prescribed in such a way that minimises fatigue between modes of training and optimises the quality of endurance training sessions. Therefore, this review will provide considerations for concurrent training prescription for endurance development based on scientific evidence. Furthermore, recommendations will be provided for future research by identifying training variables that may impact on endurance development as a result of concurrent training.

The Effects of Superset Configuration on Kinetic, Kinematic, and Perceived Exertion in the Barbell Bench Press

Weakley, JJS, Till, K, Read, DB, Phibbs, PJ, Roe, G, Darrall-Jones, J, and Jones, BL. The effects of superset configuration on kinetic, kinematic, and perceived exertion in the barbell bench press. J Strength Cond Res 34(1): 65-72, 2020-Training that is efficient and effective is of great importance to an athlete. One method of improving efficiency is by incorporating supersets into resistance training routines. However, the structuring of supersets is still unexplored. Therefore, the purpose of this study was to assess the effects of agonist-antagonist (A-A), alternate peripheral (A-P), and similar biomechanical (SB) superset configurations on rate of perceived exertion (RPE), kinetic and kinematic changes during the bench press. Ten subjects performed resistance training protocols in a randomized-crossover design, with magnitude-based inferences assessing changes/differences within and between protocols. Changes in rate of perceived exertion were very likely and almost certainly greater in the A-P and SB protocols when compared with the A-A, whereas all superset protocols had very likely to almost certain reductions in mean velocity and power from baseline. Reductions in mean velocity and power were almost certainly greater in the SB protocol, with differences between the A-A and A-P protocols being unclear. Decreases in peak force were likely and almost certain in the A-A and SB protocols respectively, with changes in A-P being unclear. Differences between these protocols showed likely greater decreases in SB peak forces when compared to A-A, with all other superset comparisons being unclear. This study demonstrates the importance of exercise selection when incorporating supersets into a training routine. It is suggested that the practitioner uses A-A supersets when aiming to improve training efficiency and minimize reductions in kinetic and kinematic output of the agonist musculature while completing the barbell bench press.

Effects of rest interval array on training volume, perceived exertion, neuromuscular fatigue, and metabolic responses during agonist-antagonist muscle alternative training

BACKGROUND

Agonist-antagonist muscle superset (SS) and paired-set (PS) strength training protocols enable the completion of training activities within a shorter period of time than traditional set. The purpose of this study was to investigate the effects of PS and SS through total volume (TV), set volume (SV), blood lactate concentration (LAC), rating of perceived exertion (RPE), and neuromuscular fatigue index (FInsm5).

METHODS

Eleven males who train recreationally performed PS and SS consisting of bent-over row (BOR) and bench press (BP). In performing the PS, a single bout of BOR was followed by a rest interval of 60 seconds, the BP was then performed and followed by another rest interval of 60 seconds. When the SS was performed, a single bout of BOR and a single bout of BP were performed consecutively and followed by a single rest interval of 120 seconds. The exercise configurations were repeated until five sets were completed. The TV was calculated by multiplying the number of successful repetitions and the load. The LAC and RPE were measured at predetermined times. Electromyographic signals were recorded for use in the FInsm5 calculation.

RESULTS

The RPE indicated that PS was significantly lower than SS (P<0.01). No significant differences between PS and SS were discovered in SV, TV, LAC, and FInsm5.

CONCLUSIONS

This study demonstrates that PS has lower perceived exertion than SS when agonist-antagonist strength training protocols are selected as the training structure.

Comparison of blood lactate and perceived exertion responses in two matched time-under-tension protocols

Purpose

The aim of this study was to compare the concentration of blood lactate [bLa-] and the subjective perception of exertion of trained men in a moderate repetition protocol (MRP) versus a high repetition protocol (HRP) equated for time under tension.

Methods

A sample of 40 healthy young men (aged, 23.2 ± 4.0 years; height, 177.3 ± 7.0 cm; BMI, 24.3 ± 2.2) performed two sessions of 8 sets of bicep curls with a one-week recovery interval between the trials. In the HRP protocol, 20 repetitions were performed with a cadence of 2 seconds of eccentric and 1 second of concentric, while in the MRP protocol 10 repetitions were performed with 4 seconds of eccentric and 2 seconds of concentric. Cadences were controlled by a metronome. At the beginning and end of each of the sessions, blood lactate was taken at 2, 15, and 30 minutes, and rating of perceived exertion (OMNI-RES) was assessed immediately after completion of each session.

Results

There were [bLa-] differences between protocols in the MRP 2 min, (5.2 ±1.4); 15 min, (3.2 ±1.2); 30 min, (1.9 ±0.6); p< 0.05, and the HRP 2 min, (6.1 ±1.6); 15 min, (3.7 ±1.1); 30 min, (2.2 ±0.6); p<0.01. OMNI-RES was higher in HRP, (8.8 ±0.7) than in MRP, (7.7 ±0.9). Additionally, a correlation was found between the RPE and [bLa-] values in the HRP protocol (rs = 0.35, p < 0.01).

Conclusions

Training protocols with high times under tension promote substantial increases in metabolic stress, however, our findings indicate that HRP generates more [bLa-] than MRP. In addition, there were higher RPE values in the HRP protocol compared to MRP in single-joint exercises.

Is Tensiomyography-Derived Velocity of Contraction a Sensitive Marker to Detect Acute Performance Changes in Elite Team-Sport Athletes?

PURPOSE

To examine the variations in the velocity of contraction (Vc) assessed using tensiomyography, vertical jumping ability, and sprinting speed induced by 4 different exercise protocols (ie, strength, sprint, plyometric, and technical training sessions) in 14 male national-team rugby players (age 21.8 [2.6] y, weight 83.6 [8.5] kg, and height 177.4 [6.7] cm).

METHODS

Physical tests were conducted immediately before and after 4 distinct workouts in the following order: tensiomyography in the rectus femoris and biceps femoris muscles, squat and countermovement jumps, and 30-m sprint velocity. To analyze the differences in the assessed variables before and after each training session, the differences based on magnitudes were calculated.

RESULTS

After strength and plyometric workouts, the players presented possible to almost certain impairments in sprint and jump performance and in the Vc of the rectus femoris (effect sizes 0.26-0.64). After the sprint-training session, possible to very likely decreases were observed in the squat jump, 30-m sprint, and Vc of the biceps femoris (effect sizes 0.21-0.44). By contrast, after the technical training, athletes demonstrated a possible increase in the squat jump and Vc in both muscles examined (effect sizes 0.13-0.20).

CONCLUSIONS

The main finding of this research is that, for the vast majority of results, the direction of changes observed in Vc were the same as those observed in performance assessments. This suggests that Vc might be used as a sensitive marker of acute variations in speed and power performance of elite team-sport athletes.

Application of velocity loss thresholds during free-weight resistance training: Responses and reproducibility of perceptual, metabolic, and neuromuscular outcomes

The aim of this study was to investigate the differences and long-term reliability in perceptual, metabolic, and neuromuscular responses to velocity loss resistance training protocols. Using a repeated, counterbalanced, crossover design, twelve team-sport athletes completed 5-sets of barbell back-squats at a load corresponding to a mean concentric velocity of ~0.70 m·s^-1. On different days, repetitions were performed until a 10%, 20% or 30% velocity loss was attained, with outcome measures collected after each set. Sessions were repeated after four-weeks. There were substantial between-protocol differences in post-set differential ratings of perceived exertion (dRPE, i.e., breathlessness and leg muscles, AU) and blood lactate concentration (B[La], mmol·L^-1), such that 30%>20%>10% by small to large magnitudes. Differences in post-set countermovement jump (CMJ) variables were small for most variables, such that 30%<20%<10%. Standard deviations representing four-week variability of post-set responses to each protocol were: dRPE, 8-11; B[La], 0.8-1.0; CMJ height, 1.6-2.0; CMJ PPO, 1.0-1.8; CMJ PCV, 0.04-0.06; CMJ 100ms-Impulse, 5.7-11.9. Velocity loss thresholds control the magnitude of perceptual, metabolic, and neuromuscular responses to resistance training. For practitioners wanting to reliably prescribe training that can induce a given perceptual, metabolic, or neuromuscular response, it is strongly advised that velocity-based thresholds are implemented.

Maximizing Muscle Hypertrophy: A Systematic Review of Advanced Resistance Training Techniques and Methods

BACKGROUND

Effective hypertrophy-oriented resistance training (RT) should comprise a combination of mechanical tension and metabolic stress. Regarding training variables, the most effective values are widely described in the literature. However, there is still a lack of consensus regarding the efficiency of advanced RT techniques and methods in comparison to traditional approaches.

METHODS

MEDLINE and SPORTDiscus databases were searched from 1996 to September 2019 for all studies investigating the effects of advanced RT techniques and methods on muscle hypertrophy and training variables. Thirty articles met the inclusion criteria and were consequently included for the quality assessment and data extraction.

RESULTS

Concerning the time-efficiency of training, the use of agonist-antagonist, upper-lower body supersets, drop and cluster sets, sarcoplasma stimulating training, employment of fast, but controlled duration of eccentric contractions (~2s), and high-load RT supplemented with low-load RT under blood flow restriction may provide an additional stimulus and an advantage to traditional training protocols. With regard to the higher degree of mechanical tension, the use of accentuated eccentric loading in RT should be considered. Implementation of drop sets, sarcoplasma stimulating training, low-load RT in conjunction with low-load RT under blood flow restriction could provide time-efficient solutions to increased metabolic stress.

CONCLUSIONS

Due to insufficient evidence, it is difficult to provide specific guidelines for volume, intensity of effort, and frequency of previously mentioned RT techniques and methods. However, well-trained athletes may integrate advanced RT techniques and methods into their routines as an additional stimulus to break through plateaus and to prevent training monotony.

The Effects of 10%, 20%, and 30% Velocity Loss Thresholds on Kinetic, Kinematic, and Repetition Characteristics During the Barbell Back Squat

PURPOSE

Prescribing resistance training using velocity loss thresholds can enhance exercise quality by mitigating neuromuscular fatigue. As little is known regarding performance during these protocols, we aimed to assess the effects of 10%, 20%, and 30% velocity loss thresholds on kinetic, kinematic, and repetition characteristics in the free-weight back squat.

METHODS

Using a randomized crossover design, 16 resistance-trained men were recruited to complete 5 sets of the barbell back squat. Lifting load corresponded to a mean concentric velocity (MV) of ∼0.70 m·s-1 (115 [22] kg). Repetitions were performed until a 10%, 20%, or 30% MV loss was attained.

RESULTS

Set MV and power output were substantially higher in the 10% protocol (0.66 m·s-1 and 1341 W, respectively), followed by the 20% (0.62 m·s-1 and 1246 W) and 30% protocols (0.59 m·s-1 and 1179 W). There were no substantial changes in MV (-0.01 to -0.02 m·s-1) or power output (-14 to -55 W) across the 5 sets for all protocols, and individual differences in these changes were typically trivial to small. Mean set repetitions were substantially higher in the 30% protocol (7.8), followed by the 20% (6.4) and 10% protocols (4.2). There were small to moderate reductions in repetitions across the 5 sets during all protocols (-39%, -31%, -19%, respectively), and individual differences in these changes were small to very large.

CONCLUSIONS

Velocity training prescription maintains kinetic and kinematic output across multiple sets of the back squat, with repetition ranges being highly variable. Our findings, therefore, challenge traditional resistance training paradigms (repetition based) and add support to a velocity-based approach.

The Effects of Augmented Feedback on Sprint, Jump, and Strength Adaptations in Rugby Union Players After a 4-Week Training Program

PURPOSE

Feedback can enhance acute physical performance. However, its effects on physical adaptation have received little attention. Therefore, the purpose of this study was to determine the effect of feedback during a 4-wk training program on jump, sprint, and strength adaptations.

METHODS

A total of 28 semiprofessional male rugby union players were strength-matched into 2 groups (feedback and nonfeedback). During the 4-wk training program, the Feedback group received immediate, objective feedback on (1) mean concentric velocity during resistance training repetitions, (2) distance feedback for standing broad jumps, and (3) time for sprints. The Nonfeedback group was not provided additional information. Across the 4-wk mesocycle, subjects completed 3 strength and conditioning sessions per week. Countermovement jump, standing long jump, 10- and 20-m sprint, and 3-repetition-maximum barbell back squat and bench press were measured before and after the training intervention. Magnitude-based inferences assessed meaningful changes within and between groups.

RESULTS

The Feedback group showed small to moderate improvements in outcome measures, whereas the Nonfeedback group demonstrated trivial to small improvements. Improvements in countermovement-jump relative peak power (effect size ± 90% confidence limits: 0.34 ± 0.42), 10-m (0.20 ± 0.35) and 20-m sprints (0.40 ± 0.21), and 3-repetition-maximum back squats (0.23 ± 0.17) were possibly to likely greater for the Feedback condition than for Nonfeedback.

CONCLUSIONS

Providing augmented feedback during strength and conditioning routines can enhance training adaptations compared with athletes who do not receive feedback. Consequently, practitioners should consider providing kinematic outputs, displacement, or sprint time at the completion of each repetition as athletes train.

Neuromuscular responses for resistance training sessions adopting traditional, superset, paired set and circuit methods

BACKGROUND

A challenging aspect of research in sports science is designing and conducting studies that simulate actual workout scenarios, especially with application to resistance training (RT). Therefore, the purpose of this study was to compare the effects of RT sessions performed in differing workout formats on myoelectric activity, strength performance, and metabolic markers (creatine kinase, lactate dehydrogenase, blood lactate) over 24, 48 and 72 hours post-workout.

METHODS

Twenty-two trained men (25.2±4.1 years, 182.1±12.3 cm and 91.2±5.9 kg) performed the following four training protocols with 10-repetition maximum loads in random order: 1) traditional set (TS): three sets were performed in succession for the barbell bench press (BP), lat pulldown (LPD), 45° incline bench press (BP45), seated close-grip row (SCR), triceps extension (TE) and biceps curl (BC) on a pulley; 2) paired set (PS): three paired sets were performed as follows: BP-LPD, BP45-SCR, and TC-B; 3) super-set (SS): similar to the PS protocol, but without rest between paired exercises; 4) circuit training (CT): one set of each exercise was performed sequentially three times.

RESULTS

The results showed greater total volume under the SS (8063.2±2270.5 kg) protocol versus the TS (7356.8±2279.7 kg). Total work (repetitions) was also significantly greater for the SS and CT protocols versus the TS (P<0.05).

CONCLUSIONS

Therefore, the practitioners should consider utilizing the SS method during time-constrained periods with the goal to achieve greater training volume in time-efficient manner versus the TS, PS and CT methods.

Repeated Bouts of Advanced Strength Training Techniques: Effects on Volume Load, Metabolic Responses, and Muscle Activation in Trained Individuals

This study investigated the effects of advanced training techniques (ATT) on muscular responses and if performing a second training session would negatively affect the training stimulus. Eleven strength-trained males performed a traditional strength training session (TST) and four different ATT: pre-exhaustion A (PE-A), pre-exhaustion B (PE-B), forced repetitions (FR), and super-set (SS). On day 1, SS produced lower volume load than TST, FR, and PE-B (−16.0%, p ≤ 0.03; −14.9, p ≤ 0.03 and −18.2%, p ≤ 0.01, respectively). On day 2, SS produced lower volumes than all the other ATT (−9.73–−18.5%, p ≤ 0.03). Additionally, subjects demonstrated lower perceived exertion on day 1 compared to day 2 (6.5 ± 0.4 AU vs. 8.7 ± 0.3 AU, p = 0.0001). For blood lactate concentration [La-] on days 1 and 2, [La-] after the tenth set was the highest compared to all other time points (baseline: 1.7 ± 0.2, fifth-set: 8.7 ± 1.0, tenth-set 9.7 ± 0.9, post-5 min: 8.7 ± 0.7 mmol∙L⁻¹, p ≤ 0.0001). Acute muscle swelling was greater immediately and 30-min post compared to baseline (p ≤ 0.0001). On day 2, electromyography (EMG) amplitude on the clavicular head of the pectoralis major was lower for SS than TST, PE-A, and PE-B (−11.7%, p ≤ 0.01; −14.4%, p ≤ 0.009; −20.9%, p = 0.0003, respectively). Detrimental effects to the training stimulus were not observed when ATT (besides SS) are repeated. Strength trained individuals can sustain performance, compared to TST, when they are using ATT in an acute fashion. Although ATT have traditionally been used as a means to optimize metabolic stress, volume load, and neuromuscular responses, our data did not project differences in these variables compared to TST. However, it is important to note that different ATT might produce slight changes in volume load, muscle excitation, and fluid accumulation in strength-trained individuals from session to session.

Strength-Endurance Training Reduces the Hamstrings Strength Decline Following Simulated Football Competition in Female Players

Hamstring strains are the most common injury in multiple sprint sports, with inadequate eccentric hamstring strength and fatigue identified as important risk factors. Resistance training interventions aimed at reducing injury risk typically focus on the development of maximum strength, while little is known about the impact of training on hamstring fatigue resistance. The present study compared the effects of strength endurance (SE) with a strength intervention (S) on the eccentric hamstring strength decline induced by a simulated soccer match. Twenty-one female soccer players were randomly assigned to a S group (n = 10) or a SE group (n = 11). Hamstrings and quadriceps isokinetic concentric and eccentric peak torque (PT) were assessed at 120°.s^-1 and hamstrings-to-quadriceps ratio (HEcc:QCon) calculated, pre- and immediately post a 90-min simulated match (BEAST90). This was repeated following a 7-week intervention of either three to five sets of 6RM leg curl and stiff-leg deadlift with 3-min inter-set rest (S), or the same exercises performed using three sets of 12–20 RM with 45–90 s inter-set rest (SE). At baseline, the simulated match led to significant declines in hamstrings eccentric peak torque (EccPT) in both groups in both dominant (D) and non-dominant (ND) legs [SE: (D: -15.5, ND: -15.6%), P = 0.001 to 0.016; S: (D: -12.3%, ND: -15.5%), P = 0.001 to 0.018]. After the 7-week intervention, we observed a group^∗intervention^∗match interaction such that there was no significant decline in EccPT in the SE group following the simulated match (D: 5.3%, ND: 2.0%), but there remained significant declines in the S group (D: -14.2%, ND: -15.5%, P = 0.018–0.001). Similarly, in the SE group, there was a significant decrease in the HEcc:QCon in D before (-14.2%, P = 0.007), but not after the training intervention, whereas declines were observed in the S group both at baseline, and following the intervention (D: -13.9%, ND: -15.6%, P = 0.045). These results demonstrate that SE training can reduce the magnitude of the EccPT decline observed during soccer competition. As inadequate eccentric strength and fatigue are both risk factors for hamstring injury, SE training should be considered along with the development of peak eccentric strength, as a component of programs aimed at reducing injury risk in multiple-sprint sports.