Comparison of resistance training vs static stretching on flexibility and maximal strength in healthy physically active adults, a randomized controlled trial.

BACKGROUND: The aim of the present study was to compare the effects of resistance training through full range of motion and static stretching (SS) of the hip and lower back extensors on flexibility and strength in healthy, physically active, adults. METHODS: Eighteen participants (age: 24.2 ± 3.0 years, body mass: 71.3 ± 8.9 kg, height: 172.8 ± 7.5 cm) were randomly assigned to either a Resistance Training (RT) (n = 6), SS (n = 6), or control (CON) group (n = 6). The sit & reach (S&R) flexibility test and maximum isometric straight legged deadlift (ISLDL) at 95% and 50% range of motion (ROM) were tested pre- and post-intervention with significance set at p < 0.05. Both groups conducted four to eight sets per session. Within each set, the RT group performed eight repetitions each lasting four seconds, while the SS group stretched continuously for 32 s. The rest periods between each set were 60-90 s. Consequently training volume and rest times were matched between the groups. RESULTS: The RT and SS groups achieved significant, large magnitude improvements in the S&R test compared to the CON group (p < 0.01 g = 2.53 and p = 0.01, g = 2.44), but no differences were observed between the RT and SS groups (p = 1.00). Furthermore, the RT group demonstrated a larger improvement in 50% and 95% ROM ISLDL compared to SS (p < 0.01, g = 2.69-3.36) and CON (p < 0.01, g = 2.44-2.57). CONCLUSION: Resistance training through a full ROM was equally effective as SS for improving S&R flexibility, but improved hip- and lower back extensor strength more than SS and the CON. The authors recommend using large ROM resistance training to improve hip and lower back extensor flexibility and muscle strength. TRIAL REGISTRATION: ISRCTN88839251, registered 24. April 2024, Retrospectively registered.

Effects of Load and Focus of Attention on Mechanical Parameters During Bench-Press Throw in Resistance-Trained Men.

PURPOSE: Power output is dependent on the load used during exercise such as bench-press throw (BPT). Attentional focus (external [EXT] vs internal [INT]) during exercise significantly modulates power performance. The purpose of the present study was to examine the effects of load and attentional focus on mechanical parameters during BPT. METHODS: In a crossover study, 31 resistance-trained men (mean age 23.5 [3.0] y) performed BPT at 30% (light), 50% (moderate), and 70% (heavy) of 1-repetition maximum (1-RM) using an INT or EXT focus of attention in randomized order. A linear encoder was used to identify barbell vertical displacement, throw time, peak/average velocity, force, and power during the concentric lifting phase. RESULTS: Statistical analysis revealed significant load × focus interaction effects for velocity and vertical displacement (P ≤ .045; 0.66 ≤ d ≤ 0.89). Post hoc analyses indicated significantly larger velocities and displacements at 30% and 70% of 1-RM in favor of EXT (P ≤ .038; 0.79 ≤ d ≤ 1.13) but similar values at 50% of 1-RM (P > .05). Furthermore, significant main effects of load were found for throw time, force, and power (P < .001; 4.20 ≤ d ≤ 14.0). While time and force gradually increased with higher loads (P < .001; 1.45 ≤ d ≤ 14.0), power output was larger at 50% compared with 30% and 70% 1-RM (P < .001; 3.09 ≤ d ≤ 7.07), irrespective of attentional focus. CONCLUSIONS: The present findings indicated that practitioners may use EXT over INT attentional focus to enhance velocity and vertical displacement during BPT at light and heavy loads (ie, 30% and 70% 1-RM). At moderate loads (ie, 50% 1-RM), mechanical bench-press parameters appear to be less affected by attentional focus.

The Connection Between Resistance Training, Climbing Performance, and Injury Prevention.

BACKGROUND: Climbing is an intricate sport composed of various disciplines, holds, styles, distances between holds, and levels of difficulty. In highly skilled climbers the potential for further strength-specific adaptations to increase performance may be marginal in elite climbers. With an eye on the upcoming 2024 Paris Olympics, more climbers are trying to maximize performance and improve training strategies. The relationships between muscular strength and climbing performance, as well as the role of strength in injury prevention, remain to be fully elucidated. This narrative review seeks to discuss the current literature regarding the effect of resistance training in improving maximal strength, muscle hypertrophy, muscular power, and local muscular endurance on climbing performance, and as a strategy to prevent injuries. MAIN BODY: Since sport climbing requires exerting forces against gravity to maintain grip and move the body along the route, it is generally accepted that a climber`s absolute and relative muscular strength are important for climbing performance. Performance characteristics of forearm flexor muscles (hang-time on ledge, force output, rate of force development, and oxidative capacity) discriminate between climbing performance level, climbing styles, and between climbers and non-climbers. Strength of the hand and wrist flexors, shoulders and upper limbs has gained much attention in the scientific literature, and it has been suggested that both general and specific strength training should be part of a climber`s training program. Furthermore, the ability to generate sub-maximal force in different work-rest ratios has proved useful, in examining finger flexor endurance capacity while trying to mimic real-world climbing demands. Importantly, fingers and shoulders are the most frequent injury locations in climbing. Due to the high mechanical stress and load on the finger flexors, fingerboard and campus board training should be limited in lower-graded climbers. Coaches should address, acknowledge, and screen for amenorrhea and disordered eating in climbers. CONCLUSION: Structured low-volume high-resistance training, twice per week hanging from small ledges or a fingerboard, is a feasible approach for climbers. The current injury prevention training aims to increase the level of performance through building tolerance to performance-relevant load exposure and promoting this approach in the climbing field.

Comparing low volume of blood flow restricted to high-intensity resistance training of the finger flexors to maintain climbing-specific strength and endurance: a crossover study.

Introduction: It is acknowledged that training during recovery periods after injury involves reducing both volume and intensity, often resulting in losses of sport-specific fitness. Therefore, this study aimed to compare the effects of high-intensity training (HIT) and low-intensity training with blood flow restriction (LIT + BFR) of the finger flexors in order to preserve climbing-specific strength and endurance. Methods: In a crossover design, thirteen intermediate climbers completed two 5-week periods of isometric finger flexors training on a hangboard. The trainings consisted of ten LIT + BFR (30% of max) or HIT sessions (60% of max without BFR) and were undertaken in a randomized order. The training session consisted of 6 unilateral sets of 1 min intermittent hanging at a 7:3 work relief ratio for both hands. Maximal voluntary contraction (MVC), force impulse from the 4 min all out test (W), critical force (CF) and force impulse above the critical force (W') of the finger flexors were assessed before, after the first, and after the second training period, using a climbing-specific dynamometer. Forearm muscle oxidative capacity was estimated from an occlusion test using near-infrared spectroscopy at the same time points. Results: Both training methods led to maintaining strength and endurance indicators, however, no interaction (P > 0.05) was found between the training methods for any strength or endurance variable. A significant increase (P = 0.002) was found for W, primarily driven by the HIT group (pretest-25078 ± 7584 N.s, post-test-27327 ± 8051 N.s, P = 0.012, Cohen's d = 0.29). There were no significant (P > 0.05) pre- post-test changes for MVC (HIT: Cohen's d = 0.13; LIT + BFR: Cohen's d = -0.10), CF (HIT: Cohen's d = 0.36; LIT + BFR = 0.05), W` (HIT: Cohen's d = -0.03, LIT + BFR = 0.12), and forearm muscle oxidative capacity (HIT: Cohen's d = -0.23; LIT + BFR: Cohen's d = -0.07). Conclusions: Low volume of BFR and HIT led to similar results, maintaining climbing-specific strength and endurance in lower grade and intermediate climbers. It appears that using BFR training may be an alternative approach after finger injury as low mechanical impact occurs during training.

Comparison of finger flexor resistance training, with and without blood flow restriction, on perceptional and physiological responses in advanced climbers.

This study compared perceptional and physiological responses of finger flexor exercise performed with free flow and blood flow restriction (BFR). Thirteen male advanced climbers completed three sessions of finger flexor resistance exercise at (1) 40% of MVC (Low) and (2) 75% of MVC (High) and (3) BFR at 40% of MVC (Low + BFR) in a randomized and counterbalanced order. Rate of perceived exertion for effort (RPE) and discomfort (RPD), session pleasure/displeasure (sPDF), exercise enjoyment (EES), lactate concentration and oxygen saturation were recorded after the last set. Both low-intensity sessions induced higher RPD than High (p = 0.018-0.022, ES = 1.01-1.09) and High was perceived as more enjoyable than Low-BFR (p = 0.031, ES = 1.08). No differences were found for RPE or sPDF (p = 0.132-0.804). Lactate was elevated more after High than the Low-sessions (p < 0.001, ES = 1.88-2.08). Capillary oxygen saturation was lower after Low + BFR compared to the other sessions (p = 0.031, ES = 1.04-1.27). Finally, the exercise volume was greater in Low compared to High (p = 0.022, ES = 1.14) and Low + BFR (p = 0.020, ES = 0.77). In conclusion, among advanced male climbers, performing Low + BFR led to a similar exercise volume but was perceived as more discomforting and less enjoyable compared to High. The Low session yielded similar responses as the Low + BFR but required a much greater exercise volume.

Effects of climbing- and resistance-training on climbing-specific performance: a systematic review and meta-analysis.

The objective of this systematic review and meta-analysis was to examine the effects of climbing and climbing-and-resistance-training on climbing performance, and strength and endurance tests. We systematically searched three databases (SPORTDiscus, SCOPUS, and PubMed) for records published until January 2021. The search was limited to randomized-controlled trials using active climbers and measuring climbing performance or performance in climbing-specific tests. Data from the meta-analysis are presented as standardized difference in mean (SDM) with 95% confidence intervals (95% CI). Eleven studies are included in the systematic review and five studies compared training to a control group and could be meta-analyzed. The overall meta-analysis displayed an improvement in climbing-related test performance following climbing-specific resistance training compared to only climbing (SDM = 0.57, 95%CI = 0.24-0.91). Further analyses revealed that finger strength (SDM = 0.41, 95%CI 0.03-0.80), rate of force development (SDM = 0.91, 95%CI = 0.21-1.61), and forearm endurance (SDM = 1.23, 95%CI = 0.69-1.77) were improved by resistance-training of the finger flexors compared to climbing training. The systematic review showed that climbing performance may be improved by specific resistance-training or interval-style bouldering. However, resistance-training of the finger flexors showed no improvements in strength or endurance in climbing-specific tests. The available evidence suggests that resistance-training may be more effective than just climbing-training for improving performance outcomes. Importantly, interventional studies including climbers is limited and more research is needed to confirm these findings.

Does relative strength influence bench press kinematics in resistance-trained men?

The aim of the present study was to examine whether relative strength influences lifting kinematics (e.g., lifting time, barbell velocity, vertical displacement) during the bench press (BP) exercise with healthy men. Loaded BP 6-repetition maximum normalized to body mass (i.e., relative strength) was examined in 110 resistance-trained men (age: 22.9 ± 2.5 years, height: 180.9 ± 6.9 cm, body mass: 80.3 ± 7.9 kg), by analysing lifting kinematics using a linear encoder. According to relative BP strength, subjects were classified as beginners, recreationally trained, intermediate, and advanced. Results showed that in the intermediate (p = 0.004, ES = 0.85) and advanced (p = 0.016, ES = 0.81) groups barbell velocity was lower in the sticking region of the BP action, compared with beginners, however there were no significant differences between groups for vertical displacement (p = 0.122-1.000) and lifting time (p = 0.052-1.000). These findings suggest that greater relative strength improves the capacity to perform the eccentric but not the concentric phase of BP. Enhanced barbell lowering indicates that the sticking region is caused by a high demand for eccentric force production during biomechanically disadvantageous conditions.

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.

Comparing the effects of variable and traditional resistance training on maximal strength and muscle power in healthy adults: A systematic review and meta-analysis.

OBJECTIVES: The aim of the study was to aggregate different effects between variable resistance training and traditional resistance training on maximal muscle strength and muscle power and identify potential sex- and training program-related moderator variables. DESIGN: Meta-analysis. METHODS: A systematic literature search was conducted in SPORTDiscus, PubMed, and Web of Science. Interventions were included if they compared variable resistance training and traditional resistance training in healthy adults and examined the effects on measures of maximal muscle strength and/or muscle power of the lower and/or upper body. A random-effects model was used to calculate weighted and averaged standardized mean differences. Additionally, univariate sub-group analyses were independently computed for sex and training-related moderator variables. RESULTS: Seventeen studies comprising a total of 491 participants (341 men and 150 women, age 18-37 years) were included in the analyses. In terms of maximal muscle strength, there were no statistically significant differences between variable resistance training and traditional resistance training for the lower (p = 0.46, standardized mean difference = -0.10) or the upper body (p = 0.14, standardized mean difference = -0.17). Additionally, there were no significant training-related differences in muscle power for the lower (p = 0.16, standardized mean difference = 0.21) or upper body (p = 0.81, standardized mean difference = 0.05). Sub-group analyses showed a significant moderator effect for training period and repetitions per set for maximal muscle strength in the lower body (p = 0.03-0.04) with larger strength gains following traditional resistance training when performing more repetitions per set (p = 0.02, standardized mean difference = 0.43). No other significant sub-group effects were found (p = 0.18-0.82). CONCLUSIONS: Our results suggest that variable resistance training and traditional resistance training are equally effective in improving maximal muscle strength and muscle power in healthy adults.

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.

Differences in Upper-Body Peak Force and Rate of Force Development in Male Intermediate, Advanced, and Elite Sport Climbers.

The aim of this study was to investigate the difference in climbing-specific strength and rate of force development (RFD) between intermediate, advanced, and elite male sport climbers. Seventy-eight male climbers were recruited and divided into groups based on the International Rock Climbing Research Association (IRCRA) numerical (1-32) grading system (intermediate (10-17) group (IG; n = 28)), advanced (18-23) group (AG; n = 30) and elite (24-27) group (EG; n = 20). Peak force (F peak) and average force (F avg) were measured while performing an isometric pull-up on a 23 mm thick campus rung. RFD was calculated from the onset of force to maximal peak force. The elite group performed better in all test parameters than the advanced (F peak: 39.7%, ES = 1.40, p < 0.001; F avg: 45.6%, ES = 4.60, p < 0.001; RFD: 74.9%, ES = 1.42, p = 0.001) and intermediate group (F peak: 95.7%, ES = 2.54, p < 0.001, F avg: 131.1%, ES = 5.84, p < 0.001, RFD: 154.4%, ES = 2.21, p = 0.001). Moreover, the advanced group demonstrated greater F peak (40.1%, ES = 1.24, p < 0.001), F avg (59.1%, ES = 1.57, p < 0.001) and RFD (45.5%, ES = 1.42, p = 0.046), than the intermediate group. Finally, climbing performance displayed strong correlations with F peak (r = 0.73, p < 0.001) and F avg (r = 0.77, p < 0.001), and a moderate correlation with RFD (r = 0.64, p < 0.001). In conclusion, maximal force and RFD in a climbing specific test are greater among climbers on higher performance levels. Independent of climbing level there is a moderate-to-strong association between maximal and rapid force production and climbing performance.

The Acute Effects of Attaching Chains to the Barbell on Kinematics and Muscle Activation in Bench Press in Resistance-Trained Men.

The aim of the study was to investigate the acute effects of attaching chains on barbell kinematics and muscle activation in the bench press. Twelve resistance-trained men (height: 1.79 ± 0.05 m, weight: 84.3 ± 13.5 kg, one repetition maximum (1-RM) bench press of 105 ± 17.1 kg) lifted three repetitions of bench press in three conditions: (1) conventional bench press at 85% of 1-RM and bench press with chains that were (2) top-matched and (3) bottom-matched with the resistance from the conventional resistance lift. Barbell kinematics and the muscle activity of eight muscles were measured at different heights during lowering and lifting in the three conditions of the bench press. The main findings were that barbell kinematics were altered using the chains, especially the 85% bottom-matched condition that resulted in lower peak velocities and longer lifting times compared with the conventional 85% condition (p ≤ 0.043). However, muscle activity was mainly only affected during the lowering phase. Based upon the findings, it was concluded that using chains during the bench press alters barbell kinematics, especially when the resistance is matched in the bottom position. Furthermore, muscle activation was only altered during the lowering phase when adding chains to the barbell.

Acute Effects of Barbell Bouncing and External Cueing on Power Output in Bench Press Throw in Resistance-Trained Men.

The aims of this study were to compare power output during a bench press throw (BPT) executed with (BPTbounce) and without (BPT) the barbell bounce technique, and examine the effect of cueing different barbell descent velocities on BPT power output in resistance-trained males. In total, 27 males (age 23.1 ± 2.1 years; body mass 79.4 ± 7.4 kg; height 178.8 ± 5.5 cm; and 4.6 ± 1.9 years of resistance training experience) were recruited and attended one familiarization session and two experimental sessions (EXP 1 and EXP 2). The force-velocity profile during maximal BPT and BPTbounce (randomized order) under different loads (30-60 kg) was established (EXP 1), and the effect of varying external barbell descent velocity cues "slow, medium, and as fast as possible" (i.e., "fast") on the power output for each technique (BPT and BPTbounce) was examined (EXP 2). Comparing two BPT techniques (EXP 1), BPTbounce demonstrated 7.9-14.1% greater average power (p ≤ 0.001, ES = 0.48-0.90), 6.5-12.1% greater average velocity (p ≤ 0.001, ES = 0.48-0.91), and 11.9-31.3% shorter time to peak power (p ≤ 0.001-0.05, ES = 0.33-0.83) across the loads 30-60 kg than BPT. The cueing condition "fast" (EXP 2) resulted in greater power outcomes for both BPT and BPTbounce than "slow." No statistically significant differences in any of the power outcomes were observed between "medium" and "slow" cuing conditions for BPT (p = 0.097-1.000), whereas BPTbounce demonstrated increased average power and velocity under the "medium" cuing condition, compared to "slow" (p = 0.006-0.007, ES = 0.25-0.28). No statistically significant differences were observed in barbell throw height comparing BPT and BPTbounce under each cuing condition (p = 0.225-1.000). Overall, results indicate that both bouncing the barbell and emphasizing barbell descent velocity be considered to improve upper body power in athlete and non-athlete resistance-training programs.

The Effects of 10 Weeks Hangboard Training on Climbing Specific Maximal Strength, Explosive Strength, and Finger Endurance.

The aim of this study was to investigate the effects of 10 weeks of hangboard training (HBT) on climbing-specific maximal strength, explosive strength, and muscular endurance. In total, 35 intermediate- to advanced-level climbers (8 women and 27 men) were randomized into a hangboard training group (HBT) or a control group (CON). The HBT program consisted of two sessions of 48 min per week using the Beastmaker 1000 series hangboard, and the following application to smartphone. Both groups continued their normal climbing training routines. Pre- and post-intervention, maximal peak force, maximal average force, and rate of force development (RFD) were measured while performing an isometric pull-up on a 23 mm deep campus rung and jug holds. In addition, finger endurance was measured by performing a sustained dead-hang test on the same rung. The HBT increased peak force and average force in 23 mm rung condition, average force in jug condition, and utilization rate øl,.- in peak force to a greater extent than CON (p = 0.001-0.031, ES = 0.29-0.66), whereas no differences were detected between groups in RFD (jug or 23 mm), peak force in jug condition, utilization rate in RFD, average force or in dead-hang duration (p = 0.056-0.303). At post-test, the HBT group demonstrated 17, 18, 28, 10, 11, and 12% improvement in peak force, average force, RFD in 23 mm rung condition, average force in jug condition, utilization rate in peak force, and dead-hang duration, respectively [p = 0.001-0.006, effect size (ES) = 0.73-1.12] whereas no change was observed in CON (p = 0.213-0.396). In conclusion, 10 weeks of HBT in addition to regular climbing was highly effective for increasing maximal finger strength compared with continuing regular climbing training for intermediate and advanced climbers.

A randomized trial on the efficacy of split-body versus full-body resistance training in non-resistance trained women.

BACKGROUND: The aim of this study was to assess the efficacy of a 12-week upper/lower split- versus a full-body resistance training program on maximal strength, muscle mass and explosive characteristics. Fifty resistance untrained women were pair-matched according to baseline strength and randomized to either a full-body (FB) routine that trained all of the major muscle groups in one session twice per week, or a split-body program (SPLIT) that performed 4 weekly sessions (2 upper body and 2 lower body). Both groups performed the same exercises and weekly number of sets and repetitions. Each exercise was performed with three sets and 8-12 repetition maximum (RM) loading. Study outcomes included maximal strength, muscle mass, jump height and maximal power output. RESULTS: No between-group differences were found in any of the variables. However, both FB and SPLIT increased mean 1-RM from pre- to post-test in the bench press by 25.5% versus 30.0%, lat pulldown by 27.2% versus 26.0% and leg press by 29.2% versus 28.3%, respectively. Moreover, both FB and SPLIT increased jump height by 12.5% versus 12.5%, upper-body power by 20.3% versus 16.7% and muscle mass by 1.9% versus 1.7%, p < 0.01, respectively. CONCLUSIONS: This study did not show any benefits for split-body resistance-training program compared to full-body resistance training program on measures of maximal- and explosive muscle strength, and muscle mass. TRIAL REGISTRATION: ISRCTN81548172, registered 15. February 2022.

Muscle Strength Is Associated With Physical Function in Community-Dwelling Older Adults Receiving Home Care. A Cross-Sectional Study.

Background: Higher maximal- and explosive strength is associated with better physical function among older adults. Although the relationship between isometric maximal strength and physical function has been examined, few studies have included measures of isometric rate of force development (RFD) as a measure of explosive strength. Furthermore, little is known about the oldest old (>80 years), especially individuals who receive home care and use mobility devices. Therefore, the aim of this study was to examine the association between maximal- and explosive muscle strength with physical function in community-dwelling older adults receiving home care. Methods: An exploratory cross-sectional analysis including 107 (63 females and 43 males) community-dwelling older adults [median age 86 (interquartile range 80-90) years] receiving home care was conducted. Physical function was measured with five times sit-to-stand (5TSTS), timed 8-feet-up-and-go (TUG-8ft), preferred-, and maximal gait speed. Maximal strength was assessed as maximal isometric voluntary contraction (MVC) and explosive strength as RFD of the knee extensors. We used linear regression to examine the associations, with physical function as dependent variables and muscle strength (MVC and RFD) as independent variables. Results: MVC was significantly associated with 5TSST [standardized regression coefficient ß = -0.26 95% CI (-0.45, -0.06)], TUG-8ft [-0.6 (-0.54, -0.17)], preferred gait speed [0.39 (0.22, 0.57)], and maximal gait speed [0.45 (0.27, 0.62)]. RFD was significantly associated with 5TSST [-0.35 (-0.54, -0.17)], TUG-8ft [-0.43 (-0.60, -0.27)], preferred gait speed [0.40 (0.22, 0.57)], and maximal gait speed [0.48 (0.31, 0.66)]. Conclusions: Higher maximal- and explosive muscle strength was associated with better physical function in older adults receiving home care. Thus, maintaining and/or improving muscle strength is important for perseverance of physical function into old age and should be a priority.

Tests and Procedures for Measuring Endurance, Strength, and Power in Climbing-A Mini-Review.

The interest in climbing is rapidly growing among professional and recreational athletes and will for the first time be included in the 2021 Tokyo Olympics. The sport has also gained increased scientific attention in the past decades. Still, recommendations for testing procedures to predict climbing performance and measure training effects are limited. Therefore, the aim of this mini-review is to provide an overview of the climbing-specific tests, procedures and outcomes used to examine climbing performance. The available literature presents a variety of tests and procedures. While the reliability of some tests has been examined, measures of validity are scarce, especially for climbing-specific endurance tests. Moreover, considering the possible combinations of climbing performance levels, disciplines, and tests, substantial gaps in the literature exist. Vague descriptions of the participants in many studies (e.g., not specifying preferred discipline, performance level, experience, and regular climbing and training volume) further limit the current knowledge and challenge comparisons across studies. Regarding contraction types, dynamic strength- and power-tests are underrepresented in the literature compared to isometric tests. Studies exploring and reporting the validity and reliability of climbing-specific tests are warranted, and researchers should strive to provide a detailed description of the study populations in future research.

The Effects of Trunk Muscle Training on Physical Fitness and Sport-Specific Performance in Young and Adult Athletes: A Systematic Review and Meta-Analysis.

BACKGROUND: The role of trunk muscle training (TMT) for physical fitness (e.g., muscle power) and sport-specific performance measures (e.g., swimming time) in athletic populations has been extensively examined over the last decades. However, a recent systematic review and meta-analysis on the effects of TMT on measures of physical fitness and sport-specific performance in young and adult athletes is lacking. OBJECTIVE: To aggregate the effects of TMT on measures of physical fitness and sport-specific performance in young and adult athletes and identify potential subject-related moderator variables (e.g., age, sex, expertise level) and training-related programming parameters (e.g., frequency, study length, session duration, and number of training sessions) for TMT effects. DATA SOURCES: A systematic literature search was conducted with PubMed, Web of Science, and SPORTDiscus, with no date restrictions, up to June 2021. STUDY ELIGIBILITY CRITERIA: Only controlled trials with baseline and follow-up measures were included if they examined the effects of TMT on at least one measure of physical fitness (e.g., maximal muscle strength, change-of-direction speed (CODS)/agility, linear sprint speed) and sport-specific performance (e.g., throwing velocity, swimming time) in young or adult competitive athletes at a regional, national, or international level. The expertise level was classified as either elite (competing at national and/or international level) or regional (i.e., recreational and sub-elite). STUDY APPRAISAL AND SYNTHESIS METHODS: The methodological quality of TMT studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. A random-effects model was used to calculate weighted standardized mean differences (SMDs) between intervention and active control groups. Additionally, univariate sub-group analyses were independently computed for subject-related moderator variables and training-related programming parameters. RESULTS: Overall, 31 studies with 693 participants aged 11-37 years were eligible for inclusion. The methodological quality of the included studies was 5 on the PEDro scale. In terms of physical fitness, there were significant, small-to-large effects of TMT on maximal muscle strength (SMD = 0.39), local muscular endurance (SMD = 1.29), lower limb muscle power (SMD = 0.30), linear sprint speed (SMD = 0.66), and CODS/agility (SMD = 0.70). Furthermore, a significant and moderate TMT effect was found for sport-specific performance (SMD = 0.64). Univariate sub-group analyses for subject-related moderator variables revealed significant effects of age on CODS/agility (p = 0.04), with significantly large effects for children (SMD = 1.53, p = 0.002). Further, there was a significant effect of number of training sessions on muscle power and linear sprint speed (p ≤ 0.03), with significant, small-to-large effects of TMT for > 18 sessions compared to ≤ 18 sessions (0.45 ≤ SMD ≤ 0.84, p ≤ 0.003). Additionally, session duration significantly modulated TMT effects on linear sprint speed, CODS/agility, and sport-specific performance (p ≤ 0.05). TMT with session durations ≤ 30 min resulted in significant, large effects on linear sprint speed and CODS/agility (1.66 ≤ SMD ≤ 2.42, p ≤ 0.002), whereas session durations > 30 min resulted in significant, large effects on sport-specific performance (SMD = 1.22, p = 0.008). CONCLUSIONS: Our findings indicate that TMT is an effective means to improve selected measures of physical fitness and sport-specific performance in young and adult athletes. Independent sub-group analyses suggest that TMT has the potential to improve CODS/agility, but only in children. Additionally, more (> 18) and/or shorter duration (≤ 30 min) TMT sessions appear to be more effective for improving lower limb muscle power, linear sprint speed, and CODS/agility in young or adult competitive athletes.