Acute caffeine ingestion enhances strength performance and reduces perceived exertion and muscle pain perception during resistance exercise

Abstract

The efficacy of caffeine ingestion in enhancing aerobic performance is well established. However, despite suggestions that caffeine may enhance resistance exercise performance, research is equivocal on the effect of acute caffeine ingestion on resistance exercise performance. It has also been suggested that dampened perception of perceived exertion and pain perception might be an explanation for any possible enhancement of resistance exercise performance due to caffeine ingestion. Therefore, the aim of this study was to examine the acute effect of caffeine ingestion on repetitions to failure, rating of perceived exertion (RPE) and muscle pain perception during resistance exercise to failure. Eleven resistance trained individuals (9 males, 2 females, mean age±SD=26.4±6.4 years), took part in this double-blind, randomised cross-over experimental study whereby they ingested a caffeinated (5 mg kg^?1) or placebo solution 60 minutes before completing a bout of resistance exercise. Experimental conditions were separated by at least 48 hours. Resistance exercise sessions consisted of bench press, deadlift, prone row and back squat exercise to failure at an intensity of 60% 1 repetition maximum. Results indicated that participants completed significantly greater repetitions to failure, irrespective of exercise, in the presence of caffeine (p=0.0001). Mean±S.D of repetitions to failure was 19.6±3.7 and 18.5±4.1 in caffeine and placebo conditions, respectively. There were no differences in peak heart rate or peak blood lactate values across conditions (both p >0.05). RPE was significantly lower in the caffeine compared to the placebo condition (p=0.03) and was significantly higher during lower body exercises compared to upper body exercises irrespective of substance ingested (p=0.0001). For muscle pain perception, a significant condition by exercise interaction (p=0.027) revealed that muscle pain perception was lower in the caffeine condition, irrespective of exercise. With caffeine, pain perception was significantly higher in the deadlift and back squat compared to the bench press. However, with placebo, pain perception was significantly higher for the deadlift and back squat compared to the prone row only. Therefore, acute caffeine ingestion not only enhances resistance exercise performance to failure but also reduces perception of exertion and muscle pain.     

Acute adaptations and subsequent preservation of strength and speed measures following a Nordic hamstring curl intervention: a randomised controlled trial

This randomised controlled trial investigated changes in eccentric hamstring strength, 10m sprint speed, and change-of-direction (COD) performance immediately post Nordic hamstring curl (NHC) intervention and following a 3-week detraining period.

Fourteen male team sports athletes were randomised to a do-as-usual control group (CG; n = 7) or to a NHC intervention group (NHC; n = 7). Isokinetic dynamometry at 180°/s evaluated eccentric hamstring strength immediately post-intervention as the primary outcome measure. Secondary outcomes included 10 m sprint time and COD. Each outcome was measured, pre, immediately post-intervention and following a 3-week detraining period.

Immediately post-intervention significant group differences were observed in the NHC group for eccentric hamstring strength (31.81 Nm^?1 vs. 6.44 Nm^?1, P = 0.001), COD (?0.12 s vs. 0.20 s; P = 0.003) and sprint (- 0.06 s vs. 0.05 s; P = 0.024) performance. Performance improvements were maintained following a detraining period for COD (?0.11 s vs. 0.20 s; P = 0.014) and sprint (?0.05 s vs. 0.03 s, P = 0.031) but not eccentric hamstring strength (15.67 Nm^?1 vs. 6.44 Nm^?1, P = 0.145) These findings have important implications for training programmes designed to reduce hamstring injury incidence, whilst enhancing physical qualities critical to sport.     

Effects of coffee and caffeine anhydrous on strength and sprint performance

Caffeine and coffee are widely used among active individuals to enhance performance. The purpose of the current study was to compare the effects of acute coffee (COF) and caffeine anhydrous (CAF) intake on strength and sprint performance. Fifty-four resistance-trained males completed strength testing, consisting of one-rep max (1RM) and repetitions to fatigue (RTF) at 80% of 1RM for leg press (LP) and bench press (BP). Participants then completed five, 10-second cycle ergometer sprints separated by one minute of rest. Peak power (PP) and total work (TW) were recorded for each sprint. At least 48 hours later, participants returned and ingested a beverage containing CAF (300?mg flat dose; yielding 3–5?mg/kg bodyweight), COF (8.9?g; 303?mg caffeine), or placebo (PLA; 3.8?g non-caloric flavouring) 30 minutes before testing. LP 1RM was improved more by COF than CAF (p?=?.04), but not PLA (p?=?.99). Significant interactions were not observed for BP 1RM, BP RTF, or LP RTF (p?>?.05). There were no sprint?×?treatment interactions for PP or TW (p?>?.05). 95% confidence intervals revealed a significant improvement in sprint 1 TW for CAF, but not COF or PLA. For PLA, significant reductions were observed in sprint 4 PP, sprint 2 TW, sprint 4 TW, and average TW; significant reductions were not observed with CAF or COF. Neither COF nor CAF improved strength outcomes more than PLA, while both groups attenuated sprint power reductions to a similar degree. Coffee and caffeine anhydrous may be considered suitable pre-exercise caffeine sources for high-intensity exercise.     

Distribution of lower extremity work during clean variations performed with different effort

The purpose of this research was to investigate how lower extremity work was distributed during the pull of cleans performed lifting the barbell to the minimum height required to receive it in a full squat (minimal height clean); or with maximum effort to elevate the barbell as high as possible and receiving it in either a full (maximal effort clean) or partial (power clean) squat. Eight weightlifters screened for proficient technique performed these clean variations at 80% of one repetition maximum. Work performed on the barbell and by the lower extremity net joint moments (NJM) was computed from marker trajectories and ground reaction forces. Total barbell work, lower extremity NJM work, knee extensor work, and knee joint excursion during the second pull was lower in the minimal height clean than the maximal effort and power cleans (P < 0.05). This research demonstrates that more knee extensor work is performed in the second pull of maximal effort and power cleans compared to the minimal height clean. The larger knee extensor work performed is due to larger knee joint excursion during the second pull of the maximal effort and power cleans, but not larger knee extensor NJM.     

力量训练、有氧运动对体能类男性运动员BMI、骨骼肌含量、体脂百分比的影响

选取20名体能类男性运动员,分为力量训练组和有氧训练组进行为期8周的对照实验。实验发现不同运动对人体成分的改变效果不同,力量训练可以促进骨骼肌的增长,有氧训练可以起到降低体重、减小体脂、抑制骨骼肌增长的作用。     

Effect of carrying different military equipment during a fatigue test on shooting performance

This study investigated the effect of a 3-km walking test (3kWT) carrying different military equipment on shooting performance, rating of perceived exertion (RPE), heart rate (HR), and test time. The relative combat wear and backpack weight (as percentage of soldier’s body weight [%BW]) was reported and, along with HR, its relationship to marksmanship variables was tested. Thirty-nine Spanish Army males walked as fast as possible to complete the 3kWT in the following conditions in a randomized order: unloaded walking; wearing the combat uniform; and carrying the combat uniform plus combat backpack. A shooting test was completed before and after the 3kWT. The HR and RPE were evaluated. The marksmanship variables and HR were analysed using a two-way repeated measures ANOVA, and a repeated ANOVA was also used for 3kWT completion time and HR reserve analysis. Correlation analyses were performed between the equipment’s weight, HR, and marksmanship variables. The results showed that shooting score decreased after the 3kWT in both load conditions (p?r?=??0.35; p?=?0.04) and cleanness triggering (r?=?0.37; p?=?0.03). Correlations between HR and shooting variables were non-significant. In conclusion, wearing the Spanish Army combat wear and backpack resulted in shooting performance degradation. Furthermore, fatigue and RPE increased and this could decrease physical marksmanship and performance capacity in combat situations.     

Improvement of cellular health indicators and muscle quality in older women with different resistance training volumes

ABSTRACT

The main purpose of this study was to compare the effects of resistance training (RT) performed with different training volumes on phase angle (PhA), body water components, and muscle quality (MQ) in untrained older adult women. A second purpose was to assess the relationship between PhA and MQ. Sixty-two older adult women (68.6 ± 5.0 years, 65.2 ± 13.3 kg, 156.1 ± 6.2 cm) were randomly assigned into one of the three groups: two training groups performed either 1 set (G1S) or 3 sets (G3S), or a control group (CG). Body water components and PhA were estimated by bioelectrical impedance (BIA). MQ was determined by dividing skeletal muscle mass estimated by dual-energy absorptiometry (DXA) by total muscle strength from three exercises. After the intervention period, both training groups demonstrated improvements (P < 0.05) when compared with CON for intracellular water, total body water, PhA, and MQ. These results suggest that RT can improve PhA, body water components, and MQ after 12 weeks of RT in untrained older women, regardless of training volume. Furthermore, changes in MQ were positively correlated with changes in PhA (r = 0.60, P < 0.01).     

Effect of two different intensity distribution training programmes on aerobic and body composition variables in ultra-endurance runners

The aim of this study was to compare the effects of two different intensity distribution training programmes (polarized (POL) and threshold (THR)) on aerobic performance, strength and body composition variables in ultra-endurance runners. Twenty recreationally trained athletes were allocated to POL (n?=?11; age: 40.6?±?9.7 years; height: 175.4?±?7?cm; weight: 73.5?±?10.8?kg; fat mass 18.4?±?6.0%; VO₂max: 55.8?±?4.9?ml/kg/min) or THR group (n?=?9; age: 36.8?±?9.2 years; height: 178.5?±?4.2?cm; weight: 75.5?±?10.4?kg; fat mass 14.9?±?5.3%; VO₂max: 57.1?±?5.2?ml/kg/min) and performed the 12 weeks training programme. Both programmes had similar total time and load but a different intensity distribution (POL?=?79.8?±?2.1% in Zone 1; 3.9?±?1.9% in Zone 2; 16.4?±?1.5% in Zone 3; THR?=?67.2?±?4.6% in Zone 1; 33.8?±?4.6% in Zone 2; 0% in Zone 3). Body composition, isokinetic strength and aerobic running performance were measured before and after each programme. Both groups decreased fat mass after training (POL= Δ–11.2%; p?=?.017; ES?=?0.32; THR= Δ–18.8%; p?p?=?0.003; ES?=?0.71) and 12?km/h (Δ–4.5%; p?=?.026; ES?=?0.73) and running time to exhaustion (Δ2.4%; p?=?.011; ES?=?0.33). No changes were observed in strength and no significant differences were observed between the group in any variable. Compared with THR distribution, 12 weeks of POL training efficiently improves aerobic performance in recreational ultra-endurance runners.     

增强髋关节力量的重要性——优秀女子短跑运动员秦旺萍的训练启示

以当代短跑训练理论为指导,运用文献资料、个案研究、实验等方法对江苏省女子优秀短跑运动员秦旺萍进行增强髋关节力量训练的跟踪研究。研究认为增强髋关节力量(尤其是伸髋力量)对优秀短跑运动员具有十分重要的意义,它是当代优秀短跑选手以髋为轴高速摆动技术的重要保证,在短跑力量训练中应引起足够的重视。     

The effects of plyometric exercise on unilateral balance performance

Abstract

The purpose of this study was to determine the effects of plyometric exercise on unilateral balance performance. Nine healthy adults performed baseline measurements on the dominant limb that consisted of: a 20-s unilateral stability test on a tilt balance board, where a higher stability index represented deterioration in balance performance; isokinetic plantar flexion torque at 0.52 and 3.14 rad · s^?1; muscle soreness in the calf region; and resting plantar flexion angle. Plyometric exercise consisted of 200 counter-movement jumps designed to elicit symptoms of muscle damage, after which baseline measurements were repeated at 30 min, 24, 48, and 72 h. Perceived muscle soreness of the calf region increased significantly following the plyometric exercise protocol (F_4,32 = 17.24, P < 0.01). Peak torque was significantly reduced after the plyometric exercise protocol (F_4,32 = 7.49, P < 0.05), with greater loss of force at the lower angular velocity (F_4,32 = 3.46, P < 0.05), while resting plantar flexion angle was not significantly altered compared with baseline values (P > 0.05). The stability index was significantly increased (F_4,32 = 3.10, P < 0.05) above baseline (mean 2.3, s = 0.3) at 24 h (3.3, s = 0.4), after which values recovered. These results indicate that there is a latent impairment of balance performance following a bout of plyometric exercise, which has implications for both the use of skill-based activities and for increased injury risk following high-intensity plyometric training.     

Loaded hip thrust-based PAP protocol effects on acceleration and sprint performance of handball players

This study aimed to investigate the acute effects of two barbell hip thrust-based (BHT) post-activation potentiation (PAP) protocols on subsequent sprint performance. Using a crossover design, eighteen handball athletes performed maximal 15-m sprints before and 15s, 4min and 8min after two experimental protocols consisting of BHT loaded with either 50% or 85% 1RM (50PAP and 85PAP, respectively), in order to profile the transient PAP effects. The resulting sprint performances were significantly impaired at 15s only after the 85PAP protocol, which induced likely and very likely greater decreases compared to the 50PAP. At 4min and 8min, significant improvements and very likely beneficial effects were observed in the 10m and 15m performances following both protocols. Significant differences were found when comparing the two PAPs over time; the results suggested very likely greater performance improvements in 10m following the 85PAP after 4min and 8min, and possible greater performance improvements in 15m after 4min. Positive correlations between BHT 1RMs values and the greatest individual PAP responses on sprint performance were found. This investigation showed that both moderate and intensive BHT exercises can induce a PAP response, but the effects may differ according to the recovery following the potentiating stimulus and the individual`s strength level.     

抗阻训练对老年人肌肉力量影响的元分析

评价抗阻训练对改善老年人肌肉力量的效果,为抗阻训练处方的制定提供依据,以MEDLINE和PUBMED为文献主要来源,搜索1990~2010年间公开发表的抗阻训练对老年人肌肉力量影响的相关文献,根据纳入标准和排除标准选择合适的文献,对其进行质量评估和相关数据提取。结果对30篇文献进行元分析后发现,抗阻训练后,老年人腿部伸肌群最大力量加权均数差为6.78 kg,95%可信区间为5.92~7.64 kg,平均最大力量增加了24.2%;腿部屈肌群最大力量加权均数差为1.03 kg,95%可信区间为0.93~1.14 kg,平均最大力量增加了20.3%。卧推最大力量加权均数差为11.52 kg,95%可信区间为10.74~12.29 kg,平均增加了26.9%。说明抗阻训练是能有效改善老年人增龄性肌肉力量减退的干预手段;大强度的抗阻训练较中等强度或小强度的抗阻训练更能有效增强老年人肌肉力量。     

The effect of two different 18-week walking programmes on aerobic fitness,selected blood lipids and factor XIIa

Abstract

The purpose of this project was to evaluate the utility of low- and high-repetition maximum (RM) strength tests used to assess rowers. Twenty elite heavyweight males (age 23.7 ± 4.0 years) performed four tests (5 RM, 30 RM, 60 RM and 120 RM) using leg press and seated arm pulling exercise on a dynamometer. Each test was repeated on two further occasions; 3 and 7 days from the initial trial. Per cent typical error (within-participant variation) and intraclass correlation coefficients (ICCs) were calculated using log-transformed repeated-measures data. High-repetition tests (30 RM, 60 RM and 120 RM), involving seated arm pulling exercise are not recommended to be included in an assessment battery, as they had unsatisfactory measurement precision (per cent typical error > 5% or ICC < 0.9). Conversely, low-repetition tests (5 RM) involving leg press and seated arm pulling exercises could be used to assess elite rowers (per cent typical error ≤ 5% and ICC ≥ 0.9); however, only 5 RM leg pressing met criteria (per cent typical error = 2.7%, ICC = 0.98) for research involving small samples (n = 20). In summary, low-repetition 5 RM strength testing offers greater utility as assessments of rowers, as they can be used to measure upper- and lower-body strength; however, only the leg press exercise is recommended for research involving small squads of elite rowers.     

Effect of resistance training regimens on treadmill running and neuromuscular performance in recreational endurance runners

Abstract

The purpose of this study was to assess the effects of heavy resistance, explosive resistance, and muscle endurance training on neuromuscular, endurance, and high-intensity running performance in recreational endurance runners. Twenty-seven male runners were divided into one of three groups: heavy resistance, explosive resistance or muscle endurance training. After 6 weeks of preparatory training, the groups underwent an 8-week resistance training programme as a supplement to endurance training. Before and after the 8-week training period, maximal strength (one-repetition maximum), electromyographic activity of the leg extensors, countermovement jump height, maximal speed in the maximal anaerobic running test, maximal endurance performance, maximal oxygen uptake ([Vdot]O_2max), and running economy were assessed. Maximal strength improved in the heavy (P = 0.034, effect size ES = 0.38) and explosive resistance training groups (P = 0.003, ES = 0.67) with increases in leg muscle activation (heavy: P = 0.032, ES = 0.38; explosive: P = 0.002, ES = 0.77). Only the heavy resistance training group improved maximal running speed in the maximal anaerobic running test (P = 0.012, ES = 0.52) and jump height (P = 0.006, ES = 0.59). Maximal endurance running performance was improved in all groups (heavy: P = 0.005, ES = 0.56; explosive: P = 0.034, ES = 0.39; muscle endurance: P = 0.001, ES = 0.94), with small though not statistically significant improvements in [Vdot]O_2max (heavy: ES = 0.08; explosive: ES = 0.29; muscle endurance: ES = 0.65) and running economy (ES in all groups < 0.08). All three modes of strength training used concurrently with endurance training were effective in improving treadmill running endurance performance. However, both heavy and explosive strength training were beneficial in improving neuromuscular characteristics, and heavy resistance training in particular contributed to improvements in high-intensity running characteristics. Thus, endurance runners should include heavy resistance training in their training programmes to enhance endurance performance, such as improving sprinting ability at the end of a race.     

Effects of movement velocity and training frequency of resistance exercise on functional performance in older adults: a randomised controlled trial

Objectives: To investigate the effects that high-velocity, low-load (HVLL) and low-velocity, high-load (LVHL) resistance exercise, performed once or twice-weekly, have on indices of functional performance (primary outcome), maximal strength, and body composition (secondary outcomes) in older adults.

Methods: In a randomised, controlled, multi-armed, parallel design, 54 moderately-highly active, but resistance exercise naïve older adults (aged 60–79 years), attended baseline and post-10-week intervention assessment sessions. Physical and functional assessments were completed, and predicted one-repetition maximums (1-RM) were obtained for eight exercises. Participants were then randomised into one of five conditions: HVLL once-weekly (HVLL1: n?=?11) or twice-weekly (HVLL2: n?=?11), LVHL once-weekly (LVHL1: n?=?10) or twice-weekly (LVHL2: n?=?11), no-exercise control condition (CON: n?=?11). The HVLL conditions completed 3 sets of 14 repetitions at 40% 1-RM and the LVHL conditions, 3 sets of 7 repetitions at 80% 1-RM. In total, 50 participants completed all testing and were included in analyses.

Results: Only LVHL2 improved 30-sec chair stand performance (p?=?.035; g?=?0.89), arm curls (p?=?.011; g?=?1.65) and grip-strength (p?=?.015; g?=?0.34) compared to CON. LVHL2 improved maximal strength compared to CON for 7/8 exercises (p?p?Conclusion: Possibly due to the lower intensity nature of the HVLL conditions, LVHL, twice-weekly was most beneficial for improving functional performance and strength in moderately-highly active older adults. Therefore, we recommend that exercise professionals ensure resistance exercise sessions have sufficient intensity of effort and volume, in order to maximise functional performance and strength gains in older adults.     

Effects of weightlifting exercise,traditional resistance and plyometric training on countermovement jump performance: a meta-analysis

Jump performance is considered an important factor in many sports. Thus, strategies such as weightlifting (WL) exercises, traditional resistance training (TRT) and plyometric training (PT) are effective at improving jump performance. However, it is not entirely clear which of these strategies can enable greater improvements on jump height. Thus, the purpose of the meta-analysis was to compare the improvements on countermovement jump (CMJ) performance between training methods which focus on WL exercises, TRT, and PT. Seven studies were included, of which one study performed both comparison. Therefore, four studies comparing WL exercises vs. TRT (total n = 78) and four studies comparing WL exercises vs. PT (total n = 76). The results showed greater improvements on CMJ performance for WL exercises compared to TRT (ES_diff: 0.72 ± 0.23; _95%CI: 0.26, 1.19; P = 0.002; Δ % = 7.5 and 2.1, respectively). The comparison between WL exercises vs. PT revealed no significant difference between protocols (ES_diff: 0.15 ± 0.23; _95%CI: ?0.30, 0.60; P = 0.518; Δ % = 8.8 and 8.1, respectively). In conclusion, WL exercises are superior to promote positive changes on CMJ performance compared to TRT; however, WL exercises and PT are equally effective at improving CMJ performance.     

Maximal strength and cortisol responses to psyching-up during the squat exercise

We studied the effect of psyching-up on one-repetition maximum (1-RM) performance and salivary cortisol responses during the squat exercise. Ten men (age 21.6?±?1.4 years; mean?±?s) and ten women (age 22.4?±?2.8 years) with weight training experience of 4.5?±?2.0 years participated in this study. One-repetition maximum squats were performed on a Smith machine during each of two different intervention conditions that were counterbalanced and consisted of a free choice psych-up and a cognitive distraction. Saliva samples were obtained at the beginning of each test session and immediately after the final 1-RM attempt. No significant difference in 1-RM was identified between psyching-up (104?±?50?kg) and cognitive distraction (106?±?52?kg). Performing a 1-RM in the squat exercise significantly increased salivary cortisol concentrations during both conditions (P <?0.05). There was no significant difference in salivary cortisol responses between conditions. These results suggest that psyching-up does not increase 1-RM performance during the squat exercise in strength-trained individuals.     

Effects of high-intensity resistance circuit-based training in hypoxia on body composition and strength performance

Abstract

Hypoxic training methods are increasingly being used by researchers in an attempt to improve performance in normoxic ambients. Moreover, previous research suggests that resistance training in hypoxia can cause physiological and muscle adaptations. The primary aim of this study was to compare the effects of 8 weeks of high-intensity resistance circuit-based (HRC) training in hypoxia on body composition and strength performance. The secondary aim was to examine the effects of HRC on metabolic parameters. Twenty-eight male participants were randomly assigned to either hypoxia (Fraction of inspired oxygen [F_IO₂]?=?15%; HRC_hyp: n?=?15; age: 24.6?±?6.8 years; height: 177.4?±?5.9?cm; weight: 74.9?±?11.5?kg) or normoxia [F_IO₂]?=?20.9%; HRC_norm: n?=?13; age: 23.2?±?5.2 years; height: 173.4?±?6.2?cm; weight: 69.4?±?7.4?kg) groups. Training sessions consisted of two blocks of three exercises (Block 1: bench press, leg extension and front pull down; Block 2: deadlift, elbow flexion and ankle extension). Each exercise was performed at six repetition maximum. Rest periods lasted for 35-s between exercises, 3-min between sets and 5-min between blocks. Participants exercised twice weekly for 8 weeks, and body composition, strength and blood tests were performed before and after the training program. Lean body mass and bone mineral density significantly increased over time in the HRC_hyp (p?<?.005; ES?=?0.14 and p?<?.014; ES?=?0.19, respectively) but not in the HRC_norm after training. Both groups improved their strength performance over time (p?<?.001), but without group effect differences. These results indicate that simulated hypoxia during HRC exercise produced trivial effects on lean body mass and bone mineral density compared to normoxia.     

The effect of a familiarisation period on subsequent strength gain

Abstract

Untrained subjects can display diverse strength gain following an identical period of resistance exercise. In this investigation, 28 untrained males completed 16-weeks of resistance exercise, comprising 4-weeks familiarisation, and 12-weeks of heavy-load (80–85%) activity. High and low responders were identified by the Δ1RM (Δ one repetition maximum) observed following familiarisation (25.1 ± 1.4%, 9.5 ± 1.4%, P < 0.0001) and differences in electromyographic root mean square amplitude (ΔEMG_RMS 29.5 ± 8.3%, 2.4 ± 6.0%, P = 0.0140), and habitual and occupational activity patterns were observed between these respective groups. The strength gain (P < 0.0001) observed within high (29.6 ± 1.7%) and low (31.4 ± 2.7%) responding groups was similar during the heavy-load phase, yet ΔEMG_RMS increased (P = 0.0048) only in low responders (31.5 ± 9.3%). Retrospectively, differences (P < 0.0001) in baseline 1RM strength of high- (19.7 ± 0.9 kg) and low-responding (15.6 ± 0.7 kg) groups were identified, and a strong negative correlation with Δ1RM after 16-weeks (r ² = ?0.85) was observed. As such, baseline 1RM strength provided a strong predicative measure of strength adaptation. The ΔEMG_RMS suggests strength variability within high and low responders may be attributed to neural adaptation. However, differences in habitual endurance and occupational physical activity suggests one should consider screening not only recent resistance training, but also other modes of physical activity during participant recruitment.     

Effects of strength training on physical fitness and sport-specific performance in recreational,sub-elite,and elite rowers: A systematic review with meta-analysis

ABSTRACT

The purpose of this systematic review with meta-analysis was to examine the effects of strength training (ST) on selected components of physical fitness (e.g., lower/upper limb maximal strength, muscular endurance, jump performance, cardiorespiratory endurance) and sport-specific performance in rowers. Only studies with an active control group were included if they examined the effects of ST on at least one proxy of physical fitness and/or sport-specific performance in rowers. Weighted and averaged standardized mean differences (SMD) were calculated using random-effects models. Subgroup analyses were computed to identify effects of ST type or expertise level on sport-specific performance. Our analyses revealed significant small effects of ST on lower limb maximal strength (SMD = 0.42, p = 0.05) and on sport-specific performance (SMD = 0.32, p = 0.05). Non-significant effects were found for upper limb maximal strength, upper/lower limb muscular endurance, jump performance, and cardiorespiratory endurance. Subgroup analyses for ST type and expertise level showed non-significant differences between the respective subgroups of rowers (p ≥ 0.32). Our systematic review with meta-analysis indicated that ST is an effective means for improving lower limb maximal strength and sport-specific performance in rowers. However, ST-induced effects are neither modulated by ST type nor rowers’ expertise level.