2-minute Rest Intervals Research Articles

Increased Neuromuscular Activity, Force Output, and Resistance Exercise Volume When Using 5-Minute Compared with 2-Minute Rest Intervals Between the Sets.

McMahon, G, Best, N, Coulter, T, and Erskine, RM. Increased neuromuscular activation, force output and resistance exercise volume when using 5-minute compared with 2-minute rest intervals between the sets. J Strength Cond Res 38(9): 1527-1534, 2024-Longer rest intervals between resistance exercise (RE) sets may promote greater muscle hypertrophy and strength gains over time by facilitating the completion of greater training volume and intensity. However, little is known about the acute neuromuscular responses to RE sets incorporating longer vs. shorter rest intervals. Using a within-subject, crossover design, 8 healthy, young subjects completed 2 separate acute bouts of 4 sets of 8 × 3-s maximal isometric contractions using either a 2-minute (REST-2) or 5-minute (REST-5) rest interval between sets. Peak torque (PT) and electromyography (EMG) were measured pre and 5 minutes postexercise. Peak torque and mean torque (MT), EMG, mean, and median frequencies were measured during each set, whereas blood lactate (BLa), heart rate (HR), and rating of perceived exertion (RPE) were measured following each set. Peak torque and MT were lower ( p < 0.05) in sets 3 and 4, and sets 2-4 in REST-2 compared with REST-5, respectively. Electromyography and BL were lower and higher, respectively, in REST-2 vs. REST-5. There was no main effect of condition on HR or RPE. Pre-to-post exercise reductions in PT (-17 ± 9% vs. -4 ± 7%) and EMG (-29 ± 14% vs. -10 ± 7%) were greater ( p < 0.001) in REST-2 vs. REST-5. Total exercise volume was less in REST-2 vs. REST-5 (9,748 ± 2296 N·m -1 vs. 11,212 ± 2513 N·m -1 , p < 0.001). These results suggest that incorporating 5-minute between-set rest intervals into a resistance exercise session facilitates improved neuromuscular function, increased exercise volume, and less metabolic stress compared with 2-minute rest intervals. Thus, 5-minute rest intervals may be more efficacious for promoting muscle hypertrophy and strength gains in a chronic resistance training program.

Effects of Sprint Interval Training Surface on Physical Fitness Attributes of Collegiate Female Soccer Players: Identifying Individual Responses to Training on Grass, Sand, and Land Surfaces.

This study aimed to identify the optimal surface for sprint interval training to maximize transfer effects on physical performance measures on the grass pitch. Using a randomized controlled trial design, 40 collegiate female soccer players were equally assigned to three experimental groups performing short sprint interval training (SSIT: 4 sets of 10 repetitions with 5 seconds all-out running, with a 50-second recovery period between each effort and a 3-minute rest interval between sets) on SAND, GRASS, LAND, and a control group. Before and after a 7-week training period, participants underwent a series of field-based tests to evaluate countermovement jump (CMJ), 20-m linear sprint, Illinois change of direction (CoD) speed, Yo-Yo IR1, 2.4 km time trial, and maximal kicking distance (MKD) performance. A two-way analysis of variance with repeated measures was conducted on the data, along with Bonferroni post hoc testing. After the intervention, the control group did not show any changes, while the SAND, GRASS and LAND training groups demonstrated improvements (p = 0.001) in their performance as follows: CMJ (effect size [ES] = 1.21, 0.97, 0.64), 20-m linear sprint (ES = -0.81, -0.55, -0.41), Illinois CoD (ES = -0.72, -0.79, -0.41), Yo-Yo IR1 (ES = 1.86, 1.19, 1.12), 2.4 km time trail (ES = -0.82, -0.62, -0.49), and MKD (ES = 0.60, 0.90, 0.72), respectively. Comparative analysis of SAND, GRASS, and LAND revealed that performing SSIT on SAND results in a significantly greater gain in CMJ than LAND (p = 0.041). Analyzing individual responses to training interventions indicated that the training surface had a favorable influence on CMJ (SAND vs. LAND, p = 0.009), but on other variables no statistically significant (p > 0.05) differences were observed. Considering these findings, it is advised that strength and conditioning coaches use the SAND surface as the initial choice for SSIT sessions regarding greater gains (i.e., ES) in performance. This recommendation aims to facilitate more favorable transfer in physical fitness adaptation on a soccer grass pitch. In case of unavailability of SAND surface, GRASS surface would be a suitable alternative to enhance the physical fitness of collegiate female soccer players.

Time under tension and mechanical variables in the bench press exercise at different rest intervals

Purpose: To analyze the behavior of time under tension (TUT), total work (TW), power (PW), mean velocity (MV), and number of repetitions (NR) during the bench press exercise with distinct rest intervals. Methods: Twenty-one wrestling athletes (body mass: 81.27 ± 14.25kg; height: 1.74 ± 0.07m) completed 5 sets, each consisting of a maximum of 10 repetitions, with either a 1-minute rest interval (RI1) or a 3-minute rest interval (RI3). Results: TUT was higher in RI3 when compared to RI1 in set 5 (p&lt;0.001). NR was higher in RI3 compared to RI1 in set 3 (p=0.016), set 4 (p=0.021), and set 5 (p&lt;0.001). TW was higher in RI3 compared to RI1 in set 3 (p=0.005), set 4 (p=0.007), and set 5 (p&lt;0.001). MV was higher in RI3 compared to RI1 in set 4 (p=0.029) and set 5 (p&lt;0.001). PW was higher in RI3 compared to RI1 in set 4 (p=0.044) and set 5 (p&lt;0.001). Conclusion: The behavior of consecutive sets with a similar number of repetitions but with an increase in TUT or sets with a similar TUT but with a lower number of repetitions were found. Third set appears to be a point of performance reduction worth considering depending on the exercise's goal. Keywords: time under tension; number of repetitions; bench press; rest interval between sets; mechanical variables.

Acute Effects of Different Inter-Repetition Rest Intervals During ‘Composite’ Training on Fast Stretch-Shortening Cycle and Neuromuscular Performance in Hurling Players: A Pilot Study

One study to date has compared inter-repetition rest intervals when employing ‘composite’ training. Thus, the purpose of this study was to compare the acute effects of 2-, 3- and 4-mins ‘composite’ training inter-repetition rest intervals on fast stretch shortening cycle (SSC) and neuromuscular performance. A randomized crossover research design was employed. Drop jump (DJ), 20m sprint (with 5 and 10m splits), countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) tests were performed pre-session, post-session, and 7 days post-session to observe if supercompensation occurred. A 2-min rest interval showed enhancements in fast SSC DJ performance where supercompensation may have occurred in height, velocity, force and power (Cohen’s d = 0.22-0.55). A 3-minute rest interval elicited responses in 5 and 20m sprint performance (Cohen’s d = -0.29 to -0.30) and isometric RFD (Cohen’s d = 0.35-0.60) 7 days post-session. CMJ measures (Cohen’s d = 0.22-0.76) appeared to have experienced supercompensation when employing a 4-minute rest period. Significant (p &lt; 0.05) decreases in performance pre- to post-session were found for certain sprint, CMJ and IMTP variables. The ‘composite’ training inter-repetition rest interval used, appears dependent on the primary goal of a training cycle. However, a 3-min rest interval may be used if there are multiple goals of a training cycle due to enhancements in sprint performance, isometric RFD and CMJ height. ‘Composite’ training is a time-efficient method of enhancing jump, sprint, and maximal strength, which is suitable for practitioners working in sports such as hurling where time is limited.

How does rest Interval duration affect performance? An experiment on high-intensity sprint exercises

Introduction: The purpose of this study was to examine the effects of interval and high-intensity sprint training (RST) with different rest intervals on the respiratory function, aerobic and anaerobic power. (2) Materials and Methods: The study involved the voluntary participation of 20 male participants. The participants were divided into two groups: 2IRG (2-minute rest between repeated sprints) and 4IRG (4-minute rest between repeated sprints). The changes in the respiratory function, aerobic, and anaerobic power parameters were examined in the 2IRG and 4IRG athletes who performed two training sessions per week for 4 weeks. (3) Results: The findings indicated that there was no improvement in the respiratory function among the athletes, but there was a significant improvement in aerobic and anaerobic power parameters. However, this improvement was similar in both the 2IRG and 4IRG groups. (4) Conclusions: A 4-week high-intensity interval training program with two RST sessions per week was insufficient to elicit improvements in the respiratory function. However, RST protocols with 2-minute and 4-minute rest intervals provided similar aerobic and anaerobic benefits.

Heavier loads in flywheel exercise induce greater post-activation performance enhancement in countermovement jumps compared to heavy Smith machine squats in males.

We evaluated the effects of post-activation performance enhancement through flywheel exercise with varying inertial loads compared to traditional resistance exercise on countermovement jump performance and muscle recruitment. In a randomized crossover design, 13 trained men completed four main experimental trials after three familiarization sessions. These conditions included a traditional trial consisting of 5 sets of 1 repetition using the Smith machine (SM) squat at 90% 1RM, and three flywheel ergometer trials. Each flywheel protocol consisted of 3 sets of 8 repetitions with 3-minute rest intervals between sets, utilizing one of three inertial loads (0.0465, 0.0784, and 0.1568 kg · m2 for light, moderate, and heavy, respectively). Participants performed countermovement jumps before (baseline), immediately after (0 minute), and at the fourth (+4 minutes), eighth (+8 minutes), and twelfth (+12 minutes) minute following exercise. Compared to baseline, jump height was higher at +4 minutes for SM squats (p = 0.009). All flywheel conditions exhibited higher jump heights at +4 minutes (p < 0.05), +8 minutes (p < 0.001), and +12 minutes (p < 0.001) compared to baseline. Additionally, moderate and heavy loads resulted in higher jump heights at 0 minute (both p < 0.001). Integrated electromyographic activity values, a proxy for muscle recruitment, were significantly higher for the gluteus maximus muscle at both +8 minutes and +12 minutes for moderate (both p = 0.004) and heavy loads (p ≤ 0.002) compared to SM squats. Overall, flywheel protocols produce greater post-activation performance enhancement, extend the time window for improvement, and recruit more active musculature compared to heavy-load SM squats, particularly with heavier loads acting as a stronger preload stimulus.

A single session of hip abductors resistance exercise until failure changes shank muscle activation during landing tasks

BACKGROUND: Weakness in the hip abductors can lead to lower limb misalignment and an elevated risk of injury. This can result in compensatory mechanisms at the ankle to maintain stability. AIM: To verify the effects of a single session of hip abductors resistance exercise until failure on the foot pronation and EMG amplitude of shank muscles (peroneus longus - PL; tibialis anterior - TA) during landing tasks. METHOD: Seventeen participants completed single-leg and double-leg landings both before and after a single session of hip abductors resistance exercise until failure. The exercise consisted of four sets of 10 repetitions maximum, with a 2-minute rest interval between each set. Measurements of PL and TA EMG amplitude and degree of foot pronation were performed during landings. RESULTS: We observed a greater degree of supination of the foot during single-leg compared to double-leg landing (p=0.006), without effect of exercise. Regarding TA EMG amplitude, there was no exercise effect (p=0.951), with a higher amplitude observed in double-leg compared to single-leg landing (p=0.001). EMG amplitude of PL was higher during single-leg compared to double-leg landing (p=0.003) and the exercise significantly reduced its activation in both tasks (p=0.032). CONCLUSION: Single-leg and double-leg landings exhibited variations in mechanics and activation patterns of the distal muscles. Following a single session of hip abductors resistance exercise until failure, there was a reduction in PL activation during landing tasks. This suggests that there were neuromuscular compensations occurring distally due to alterations in the hip abductor muscles.

Acute effect of different blood flow restriction protocols on muscle damage

The aim of this study is to examine the acute effect of different blood flow restriction (BFR) protocols on muscle damage. Thirty (age 19.77±1.30 years) healthy young men were included in the study. Participants were randomly divided into three groups: Experiment 1 (continuous BFR+ barbell squat, n=10), Experiment 2 (intermittent BFR + barbell squat, n=10), and Control (only barbell squats without BFR, n=10). In 80% of their 1RMs, they performed barbell squat exercises for a total of six sets, with two repetitions in each set and a 3-minute rest interval between sets. For markers of muscle damage creatine kinase (CK), lactate dehydrogenase (LDH), aspartate transaminase (AST), and alanine transaminase (ALT), blood was drawn from the individuals twice before and immediately after the exercise. Analysis of variance in repeated measures (Repeated Measures ANOVA) test was used to analyze the data. In statistical analysis, the level of significance was accepted as p

Testosterone hormone level changes in occlusion training applied with resistance exercise in young males

This study aimed to examine the changes in the testosterone hormone level of occlusion training applied with resistance exercise in young males. The study consisted of 36 (age 19.71±1.31 years) healthy young male participants. Participants were randomly divided into three groups; experiment1 (continuous BFR, blood flow restriction, + resistance exercise), experiment2 (intermittent BFR+ resistance exercise), and control (resistance exercise only). Groups performed the squat exercise for six sets with 70% of their 1 RM, two repetitions in each set and a 3-minute rest interval between sets. For the testosterone hormone test, blood samples were taken from the participants before, after and 15 minutes after the exercise. Repeated measures analysis of variance (Repeated Measures ANOVA) was used to analyze the data. In statistical analysis, the level of significance was accepted as p&lt;.05. According to the results of the research, there was an increase in testosterone levels in the groups with continuous and intermittent BFR compared to the control group.

Order of concentric and eccentric muscle actions affects metabolic responses.

Resistance exercise provides an effective stimulus for improving the metabolic plasticity of skeletal muscle, and the type of acute muscle contraction plays an important role in determining specific responses and adaptations. The purpose of the current investigation was to examine the effect of contraction order on metabolic responses by comparing monophasic concentric and eccentric squats versus a protocol incorporating alternated concentric and eccentric repetitions. Twelve recreationally active men (21.1±1.1yr) performed three nearly identical squat protocols on separate days. Protocols varied only with contraction-type, including 4 sets × 10 reps concentric-only (CON), eccentric-only (ECC), and BOTH which alternated 5 concentric followed by 5 eccentric reps (CON-ECC; sets 1 and 3) and vice versa (ECC-CON; sets 2 and 4). The experimental trials were performed once weekly in a randomized, counter-balanced order, and expired gases were collected using a two-way non-rebreathing mask and oxygen consumption quantified with indirect calorimetry. Subjects raised (CON) and lowered (ECC) the load in 2s, and all sets (2 min) and repetitions (8 s) were separated by standardized rest intervals. From the BOTH protocol, the increase in metabolic rate was significantly greater (P≤0.05) during squats performed with CON-ECC order (0.60±0.11 L·min-1) compared to ECC-CON (0.44±0.07 L·min-1), but excess postexercise oxygen consumption (EPOC) was opposite, with significantly greater metabolic rate during the 2-minute rest intervals after ECC-CON squats (0.46±0.09 L·min-1) compared to CON-ECC (0.25±0.05 L·min-1). Metabolic rates during and after squats were significantly greater (P≤0.05) with CON (0.63±0.09; 0.49±0.10 L·min-1) compared to ECC (0.34±0.04; 0.20±0.04 L·min-1), respectively. These data present an interesting paradigm regarding the contraction-dependent metabolic responses to monophasic resistance exercise and suggest a greater EPOC following concentric versus eccentric muscle actions.

Comparison Of Glycemic Behavior Between Strength Training, HighIntensity Resistance Training (Hirt), High Intensity Interval Training (Hiit):A Case Study

Type 2 Diabetes Mellitus (DM 2) is generally a defect in insulin action and secretion and in the regulation of hepatic glucose production. Exercise to treat type 2 diabetes has had positive impacts on the lives of diabetics. The aim of this study is to analyze the effects of the glycemic curve in three different types of training: Strength Training (TF), High Intensity Resistance Training (HIRT) and Interval High Intensity Training (HIIT). The participantis a 57yearold, sedentary type 2 diabetic who under went the training method - Strength Training (ST) 60% of repetition maximum (RM), 8 to 12 repetitions, cadence 2010, the 2-minute restinterval. High Intensity Resistance Training (HIRT)protocol consisted of three sets with six repetitions at 80% of 1RM followed by rest for 20 seconds, the individual performs another series with the same load until reaching the point of failure again. The rest of one exercises and another is 2’30” , and High IntensityInterval Training (HIIT) a 5-minute warm-upmoderateload – 4 shots of 30 secondsof high intensity duration separated by 4 minutes of rest, once a week at night. Pre-study anamnesis, pre- and post-exercise glycemia were performed.The overall results were satisfactory presenting HIIT as the most effective method for acute post-exercise blood glucose reduction (reducing 29.62%, 34.25%, 38.89 and 36.11% immediatelyat 10, 20, 30 minutes afterexertionrespectively).It was concluded that physical training positively influenced the reduction of blood glucose as an acute effect, but HIIT was the most effective method.

Acute Effects of Different Rest Intervals Between Sets of Resistance Exercise on Neuromuscular Fatigue in Trained Older Women.

Jambassi Filho, JC, Gurjão, ALD, Prado, AKG, Gallo, LH, and Gobbi, S. Acute effects of different rest intervals between sets of resistance exercise on neuromuscular fatigue in trained older women. J Strength Cond Res 34(8): 2235-2240, 2020-The aim of this study was to investigate the acute effect of different rest intervals (RIs) between sets on total volume, time under tension, maximal voluntary contraction (MVC), and integrated electromyography (iEMG) activity of the vastus lateralis (VL) and vastus medialis (VM) muscles. Twenty-one resistance-trained older women (66.4 ± 4.4 years; 69.1 ± 11.4 kg; 157.5 ± 5.0 cm) completed 3 different test sessions, performed 48-72 hours apart, in a randomized and counterbalanced within-subjects design. In 2 test sessions, the participants performed 3 sets to voluntary exhaustion with loads that corresponded to 15 maximum repetitions, with either 1-minute RI (RI-1) or 3-minute RI (RI-3). In another test session, the participants remained at rest for 15 minutes. The total volume of exercise and time under tension for the RI-3 session was statistically higher (p ≤ 0.05) than the RI-1 session. Postexercise MVC for the RI-3 session showed significantly greater reductions (-7.8%; p ≤ 0.05) compared with the RI-1 and control sessions. No significant changes in postexercise iEMG activity of the VL and VM were shown for any of the sessions (all p > 0.05). The findings of this study suggest that different RIs between sets lead to different acute neuromuscular responses. The longer RI seemed to induce higher neuromuscular fatigue, likely due to higher total volume and time under tension. Thus, longer RI may be a strategy that possibly would lead to greater long-term gains in muscle strength and hypertrophy of the lower limbs in trained older women.

The Effect of Different Rest Intervals Between Agonist-Antagonist Paired Sets on Training Performance and Efficiency.

Behenck, C, Sant'Ana, H, Pinto de Castro, JB, Willardson, JM, and Miranda, H. The effect of different rest intervals between agonist-antagonist paired sets on training performance and efficiency. J Strength Cond Res 36(3): 781-786, 2022-The purpose of this study was to verify the effect of different rest intervals (RIs) between agonist-antagonist paired sets (APS) on training performance and efficiency. Eighteen recreationally trained men (age: 21.5 ± 2.1 years, body mass: 74.5 ± 10.4 kg, height: 1.75 ± 0.04 m, body mass index: 24.4 ± 3.7 kg·m-2) completed 4 sessions. During each session, a 10-repetition maximum load was used for 3 APS of Bench Row + Bench Press and Lat Pull-down + Overhead Press with RI between APS sequences of 1, 2, 3 minutes (min) or self-selected RI (SRI). Total training volume (TTV), session time and efficiency were measured in all sessions. The 1-minute RI resulted in significantly less TTV vs. the other conditions (p = 0.000). The 2-minute RI resulted in significantly less TTV vs. the 3-minute RI (p = 0.002), but the SRI was not significantly different vs. the 3-minute RI. For session time, the 1-minute RI was significantly less (p = 0.000) and the 3-minute RI was significantly greater (1-minute and 2-minute RI, p = 0.000; SRI, p = 0.010) than the other conditions. Therefore, the efficiency of the 1-minute RI was significantly greater vs. the other conditions (3-minute RI and SRI, p = 0.000; 2-minute RI, p = 0.001) and the 2-minute RI was significantly greater vs. the 3-minute RI (p = 0.001). There were no significant differences in TTV, session time, and efficiency between the 2-minute RI and SRI conditions. In conclusion, the 2-minute RI and SRI conditions may present a better cost-effectiveness. It is suggested that self-selected RI can provide better performance, whereas 2-minute RI may enable greater efficiency.

Volume Load Rather Than Resting Interval Influences Muscle Hypertrophy During High-Intensity Resistance Training.

Longo, AR, Silva-Batista, C, Pedroso, K, de Salles Painelli, V, Lasevicius, T, Schoenfeld, BJ, Aihara, AY, de Almeida Peres, B, Tricoli, V, and Teixeira, EL. Volume load rather than resting interval influences muscle hypertrophy during high-intensity resistance training. J Strength Cond Res 36(6): 1554-1559, 2022-Interset rest interval has been proposed as an important variable for inducing muscle mass and strength increases during resistance training. However, its influence remains unclear, especially when protocols with differing intervals have equalized volume. We aimed to compare the effects of long (LI) vs. short rest interval (SI) on muscle strength (one repetition maximum [1RM]) and quadriceps cross-sectional area (QCSA), with or without equalized volume load (VL). Twenty-eight subjects trained twice a week for 10 weeks. Each subject's leg was allocated to 1 of 4 unilateral knee extension protocols: LI, SI, SI with VL -matched by LI (VLI-SI), and LI with VL-matched by SI (VSI-LI). A 3-minute rest interval was afforded in LI and VSI-LI protocols, while SI and VLI-SI employed a 1-minute interval. All subjects trained with a load corresponding to 80% 1RM. One repetition maximum and QCSA were measured before and after training. All protocols significantly increased 1RM values in post-training (p < 0.0001; LI: 27.6%, effect size [ES] = 0.90; VLI-SI: 31.1%, ES = 1.00; SI: 26.5%, ES = 1.11; and VSI-LI: 31.2%, ES = 1.28), with no significant differences between protocols. Quadriceps cross-sectional area increased significantly for all protocols in post-training (p < 0.0001). However, absolute changes in QCSA were significantly greater in LI and VLI-SI (13.1%, ES: 0.66 and 12.9%, ES: 0.63) than SI and VSI-LI (6.8%, ES: 0.38 and 6.6%, ES: 0.37) (both comparisons, p < 0.05). These data suggest that maintenance of high loads is more important for strength increases, while a greater VL plays a primary role for hypertrophy, regardless of interset rest interval.

Acute Hormone Responses Subsequent to Agonist-Antagonist Paired Set vs. Traditional Straight Set Resistance Training

Miranda, H, de Souza, JAAA, Scudese, E, Paz, GA, Salerno, VP, Vigário, PdS, and Willardson, JM. Acute hormone responses subsequent to agonist-antagonist paired set vs. traditional straight set resistance training. J Strength Cond Res 34(6): 1591-1599, 2020-The purpose of this study was to compare acute hormone responses and rating of perceived exertion (OMNI-Res) subsequent to the agonist-antagonist paired set (PS) vs. the traditional straight set (TS) resistance training method. Twelve recreationally trained men (25.7 ± 4.7 years, 173 ± 6.3 cm and 71.5 ± 6.6 kg) participated in the current study. After 10 repetition maximum (RM) load determination, each subject performed the following 2 experimental sessions in random order: TS session-3 sets of 10 repetitions at 85% of 10RM for the machine seated row and barbell bench press with 2-minute rest intervals between sets; and PS-3 sets of 10 repetitions with 85% of 10RM alternating machine seated row and barbell bench press for the total of 6 PSs with 2-minute rest intervals between sets. Total testosterone (TT), free testosterone (FT), cortisol, TT/cortisol ratio, growth hormone (GH), and blood lactate concentrations were measured before workout and immediately after workout and 15 and 30 minutes after workout. The OMNI-RES was recorded at the end of each set for both exercises within each session. Under the TS session, TT significantly increased immediately post-workout vs. the pre-workout time point. For the PS session, TT significantly decreased at 30-minute post-workout vs. the immediate post-workout time point, whereas, FT significantly increased immediately post-workout and 15-minute post-workout vs. the pre-workout time point. For the TS session, GH significantly increased immediately post-workout, and at the 15- and 30-minute post-workout time points vs. the pre-workout time point, respectively. For the PS session, GH was significantly increased immediately post-workout vs. the pre-workout time point. Blood lactate significantly increased at all post-workout time points vs. the pre-workout time point under both sessions. The cortisol and TT/cortisol ratio showed no differences between sessions. In conclusion, from an acute standpoint, the TS approach showed a tendency to cause greater disruption in hormone levels, despite the lack of significant differences vs. the PS approach at all time points. However, both strategies may promote similar acute hormone responses.

Dynamic post-activation potentiation protocol improves rowing performance in experienced female rowers

ABSTRACT Post-activation potentiation likely acutely improves power-based performance; however, few studies have demonstrated improved endurance performance. Forty collegiate female rowers performed isometric potentiating (ISO), dynamic potentiating (DYN) and control (CON) warm-up protocols on a rowing ergometer, followed by a three-minute all-out test to evaluate their total distance, peak power, mean power, critical power, anaerobic working capacity (W’) and stroke rate. Fifteen-second splits were also analysed. ISO consisted of 5 × 5-second static muscle actions with the ergometer handle rendered immovable with a nylon strap, while DYN consisted of 2 × 10-second all-out rowing bouts, separated by a 2-minute rest interval. The participants were divided into high and low experience groups by median experience level (3.75 years) for statistical analysis. Significant differences (DYN > CON; p < 0.05) were found for distance (+5.6 m), mean power (+5.9 W) and W’ (+1561.6 J) for more experienced rowers (n = 19) and no differences for less experienced rowers (n = 18). Mean power in DYN was significantly greater than CON and ISO in the 15–30, 30–45, 45–60 and 60–75 second intervals independent of experience level. These results suggest that DYN may benefit experienced female rowers and that these strategies might benefit a greater power output over shorter distances regardless of experience.

Muscle activation and volume load performance of paired resistance training bouts with differing inter-session recovery periods

The purpose of this study was to examine myoelectric activity, fatigue index and volume load adopting different intersession recovery periods between repeated resistance training (RT) bouts. Fifteen recreationally-trained men participated in this study. Eight-repetition maximum (8RM) loads were determined for the bench press (BP) and 30° incline bench press (BP30) over two non-consecutive days. Three experimental protocols were performed in randomized order to examine the effect of different intersession recovery periods between repeated RT sessions for upper body muscles (pectoral major activity, anterior deltoid, triceps brachii, and biceps brachii) on volume load and myoelectric activity (SEMG), including: 24 hours (P24); 48 hours (P48); and 72 hours (P72). Each RT session consisted of performing four sets to failure for the BP and BP30 with 8-RM loads and 2-minute rest intervals between sets. The results showed that for SEMG activity, during the BP and BP30 exercises, there were no significant main effects for session, protocol, or interaction between protocols and sessions in the percentage difference between sets in activity of all muscles analyzed. Considering the overall session volume load, a significant main effect for session was noted. Volume load was significantly lower in Session 2 versus Session 1 under the P24 h protocol, without significant differences between the P48 and P72. Therefore, coaches and practitioners who need to accomplish a higher volume load without negatively impacting fatigue index and myoelectric activity for upper body muscles, should adopt recovery periods longer than 24 hours between similar RT bouts. L’objectif de cette étude était d’observer l’activité myoélectrique, l’indice de fatigue et la charge volumique en alternant différentes sessions de repos avec un entraînement en résistance (ER). Quinze hommes qui s’entraînent pour le loisir ont participé à cette étude. Huit-répétitions maximum (8RM) de charges ont été déterminées pour le développé couché (DC) et une autre session avec développé couché incliné à 30° (DC30) pendant deux jours non consécutifs. Trois protocoles expérimentaux ont été réalisé dans un ordre aléatoire afin d’observer les effets de différentes sessions de repos alternées avec les sessions d’entraînement en résistance (ER) pour les muscles du haut du corps (l’activité grand pectorale, le deltoïde antérieur, le triceps et biceps brachial) avec le volume de charge et l’activité myoélectrique (EMGS), incluant 24 h (P24) ; 48 h (P48); 72 h (P72). Chaque session ER consistait à effectuer quatres séries jusqu’à l’épuisement pour le DC et le DC30 avec 8RM des charges avec un repos de 2 minutes entre chaque série. Les résultats ont montré que pour l’activité EMGS pendant les sessions DC et DC30, il n’y avait aucun effet notoire pour session, protocole, ou bien interation entre les protocoles et les sessions dans la différence de pourcentage entre chaque série de tous les muscles analysés en activité. Considérant la globalité de la session du volume de charge, un effet notoire par session a été constaté. Le volume de charge a été significativement plus bas dans la session 2 contrairement à la session 1 avec le protocole P24 mais sans grande différence entre P48 et P72. Par conséquent, les entraîneurs et les pratiquants qui ont besoin d’atteindre un plus haut volume de charge sans conséquence négative sur l’indice de fatigue ainsi que l’activité myoélectrique pour les muscles du haut du corps, devraient mettre en place des périodes de repos plus longue que 24 h entre les mêmes séances de ER.

Effect of Rest Interval Duration on the Volume Completed During a High-Intensity Bench Press Exercise.

Hernandez, DJ, Healy, S, Giacomini, ML, and Kwon, YS. Effect of rest interval duration on the volume completed during a high-intensity bench press exercise. J Strength Cond Res 35(11): 2981-2987, 2021-Between-set rest intervals (RIs) are one of the most important variables in resistance training; however, no known research has investigated the effects of RIs greater than 5 minutes during high-intensity strength training. The purpose of this research was to examine the effects of 3 different RIs on repetition sustainability and training volume (sets × reps × resistance) during a high-intensity bench press exercise. Fifteen resistance-trained male subjects (mean ± SD, age = 25.5 ± 4.5 years, and bench press 1 repetition maximum [1RM] ratio [1RM/body mass] = 1.39 ± 0.1) completed 3 experimental sessions, during which 4 sets of the bench press were performed with 85% of 1RM load. Subjects performed the bench press using 3 different RIs in a random counterbalanced design. Data were analyzed using both a one- and two-way analysis of variance with repeated measures. As sets progressed, repetitions were significantly different (p < 0.05) between all RIs, and only the 8-minute RI (p < 0.05) allowed for the complete sustainability of repetitions over 4 consecutive sets. Subjects attained the greatest training volume (p < 0.05) using an 8-minute RI between sets compared with a 2- or 5-minute RI. Similarly, a significantly greater training volume was achieved using the 5-minute RI compared with the 2-minute RI. Resistance-trained men, with the goal of greater volume during strength training, would benefit from longer RIs, specifically using an 8-minute RI between 4 consecutive sets of a bench press exercise.

Effects of Local Vibration on Dynamic Strength Training.

Drummond, MDM, Couto, BP, Oliveira, MP, and Szmuchrowski, LA. Effects of local vibration on dynamic strength training. J Strength Cond Res 35(11): 3028-3034, 2021-The study aim was to compare the chronic effects of maximal dynamic strength training with and without the addition of local vibration (LV) on maximal force generation and hypertrophy of the elbow flexor muscles in trained subjects. Twenty men were divided into 2 groups (conventional training [CT] group and vibration training [VT] group). The CT group performed conventional maximal dynamic strength training, and the VT group performed maximal dynamic strength training with mechanical vibrations (frequency of 26 Hz and amplitude of 6 mm). CT and VT groups performed 5 sets of 3-4 repetitions, with 2-minute rest intervals between sets. The subjects trained 3 times per week for 12 weeks. After the training period, the CT group presented a significant increase in the mean 1 repetition maximum (1RM) value in the elbow flexion exercise in the orthostatic position (EFO) (7.2 ± 1.5%) (p < 0.0001) and elbow flexion exercise using the Scott bench (EFSB) (6.3 ± 1.8%) (p < 0.0001). The VT group also showed significant increases in 1RM values in the EFO (6.87 ± 0.8%) (p < 0.0001) and EFSB (6.56 ± 1.4%) (p < 0.0001). The CT group presented a significant increase in the mean maximal voluntary isometric contraction (MVIC) value after the training period (8.2 ± 2.3%) (p < 0.0001). The VT group also showed a significant increase in the mean MVIC value after training (9.1 ± 2.4%) (p < 0.0001). After the training period, both groups presented a significant increase in the mean value of elbow flexor thickness (CT = 5.6 ± 3.5%, VT = 5.1 ± 2.8%) (p = 0.001). The increases in 1RM, MVIC, and muscle thickness were statically similar between groups. Therefore, the addition of LV does not represent an additional stimulus for individuals trained in dynamic maximal strength training.

Comparison of the Affective Responses to Continuous Training and High-Intensity Interval Training Protocols: Application of the Dual-Mode Model.

Alicea, SK, Parrott, AD, Manos, TM, and Kwon, YS. Comparison of the affective responses to continuous training and high-intensity interval training protocols: application of the dual-mode model. J Strength Cond Res 35(11): 3069-3075, 2021-High-intensity interval training (HIIT) is time-efficient and has physiological benefits similar to or greater than that of continuous training (CT); however, there are mixed results regarding how HIIT protocols influence affect. The purpose of this study was to compare acute affective responses between HIIT and CT protocols over time using the Dual-Mode Model (DMM) as a theoretical framework. Subjects included 12 healthy women (aged 19-28 years) who completed a HIIT protocol consisting of a 2-minute work interval (100% V̇o2max) followed by a 2-minute rest interval (∼55% V̇o2max), and a CT protocol set at the workrate corresponding to their respiratory compensation point (RCP; ∼80% V̇o2max). Protocols were matched for average intensity, total duration, and energy expenditure. After blood pressure, anthropometrics, body composition, and V̇o2max measurements were taken, responses were recorded for affect (Feeling Scale [FS]), arousal (Felt Arousal Scale [FAS]), and rate of perceived exertion (RPE) before each protocol, during the last 10 seconds of every 2 minutes during the protocol, and at time points 2, 5, and 10 minutes after the protocol. Heart rate was also monitored continuously, and exercise enjoyment was measured before and after exercise. A repeated-measures analysis of variance revealed no significant differences in affect between CT (M = 2.5, SD = 2.1) and HIIT (M = 2.6, SD = 2.1) protocols over the duration of the exercise. There were no significant differences in mean RPE between CT (M = 12.9, SD = 2.7) and HIIT (M = 13.0, SD = 1.9) protocols (t = 0.333, p = 0.745) or in enjoyment between CT (M = 2.3, SD = 1.1) and HIIT (M = 2.0, SD = 0.9) protocols (t = -0.288, p = 0.492). In addition, based on visual inspection, the general patterning of the mean FS and FAS values between HIIT and CT was similar within the circumplex model, supporting the DMM. In conclusion, a HIIT protocol at V̇o2max and 1:1 exercise:rest interval did not result in a different affect response, perceived exertion, or enjoyment level when compared with a CT protocol at RCP.