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The ergogenic effects of simultaneous lower- and upper-body ischemic preconditioning (IPC) are a factor that has not been investigated exhaustively. Therefore, this study aimed to investigate the effects of IPC on 500 m rowing performance (time, relative peak [RPP] and mean [MPP] power output, time to peak power [TPP], and blood lactate concentration [BLa]), as well as heart rate (HR) among forty-three physically active male (n = 24) and female (n = 19) subjects. In this cross-over randomized trial, either the IPC (220 mmHg) or SHAM (20 mmHg) protocol was applied to the upper and lower limbs simultaneously for 5 min. Then, after 5 min of reperfusion, the participants performed an all-out 500 m rowing trial. During rowing, HR was recorded, and after the completion of the rowing, the BLa concentration was determined. Wilcoxon’s signed-rank test showed a significantly shorter TPP in the SHAM condition compared to under the IPC condition for females (Z = 2.415, p = 0.017), but not for males (Z = 1.914, p = 0.056). Moreover, a significant main effect of the group was reported for rowing time, BLa, RPP, and RMP (p < 0.001 for all dependent variables). No significant interactions nor a main effect of the condition were observed for rowing time, BLa, RPP, RMP, HRWP, HRMEAN, and HRMAX (p > 0.05 for all dependent variables). Simultaneous lower- and upper-body IPC led to a significant decrease in the time to peak power during the 500 m ergometer rowing trial in females but not in males. Additionally, no significant effects on the time or other power output variables, HR, or BLa concentration were registered.

The competition in powerlifting has been divided into two divisions, with gear equipment (EQ) and without gear equipment (RAW). When competing in the EQ division, additional supportive gear can be worn by the athletes, while in the RAW division such gear is not allowed. The aim of the study was to compare the results of the RAW and EQ powerlifting divisions based on the results of world championships and current world records. One-hundred and twenty powerlifters (63 men, 57 women) were included to the analysis. Post hoc analysis for the results of men’s world championships indicated significantly higher results of the barbell squat (SQ; p < 0.001; ES = 1.31), bench press (BP; p < 0.001; ES = 1.27) and deadlift (DL; p < 0.001; ES = 0.37) for EQ compared to the RAW division. Post hoc analysis for the results of women’s world championships indicated significantly higher results of the SQ (p < 0.001; ES = 1.31), BP (p < 0.001; ES = 1.13) and DL (p < 0.001; ES = 0.71) for the EQ compared to the RAW division. Post hoc analysis for men’s world record indicated significantly higher results in the SQ (p < 0.001; ES = 1.32) and BP (p < 0.001; ES = 1.24) for the EQ compared to the RAW division. Furthermore, there were no significant differences in the results of world records in the DL (p = 0.901; ES = 0.26) between the EQ and RAW divisions. Post hoc analysis for women’s world records indicated significantly higher results in the SQ (p < 0.001; ES = 1.22) and BP (p < 0.001; ES = 1.99) for the EQ compared to RAW division. The main finding of the study was that supportive gear increases maximal load lifted during powerlifting competition.

The main aim of this study was to determine whether the level of experience in strength training has a significant effect on differences in the value of exercise volume determined on time under tension (TUT) and number of repetition (REP) for a specific movement tempo. The study examined 68 men divided into groups of beginners and advanced strength trained athletes. The participants performed 5 sets of bench press (BP) at 70% 1RM using either a REG, MED or SLOW metronome guided cadence. Each set was performed to failure and with 3 min of rest between sets. Significant differences in TUT were found between the groups of beginners and advanced athletes for the slow (SLO) 6/0/4/0 tempo in set 1 (p = 0.01) and set 2 (p = 0.04), and for the regular (REG) 2/0/2/0 tempo in set 5 (p = 0.01). Significant differences were documented for total TUT between the beginners and advanced athletes for the SLO 6/0/4/0 tempo (p = 0.04). The results of ANOVA revealed significant differences in the number of repetitions between groups for the SLO 6/0/4/0 tempo in set 4 (p = 0.04) and set 5 (p = 0.04), and for the REG 2/0/2/0 tempo in set 5 (p = 0.01). The main finding of this study is that strength training experience has a significant effect on training volume, both in terms of TUT and REP at a specific constant movement tempo. Significant differences do not occur for each value of the tempo used.

This study aimed to investigate the relationships between the modified t−agility test (MAT) time and muscular strength and power of lower limb extensors, adductors (AD), and abductors (AB). Nineteen male basketball players performed: linear sprint tests at 5 m and 20 m, MAT, countermovement (CMJ) and drop jump (DJ), leg press exercise, AD and AB hip maximum isometric strength measurements. All of them were left leg dominant. The correlation analysis showed a significant, moderate to very large negative relationship between MAT test time initiated to the left and height of CMJ and DJ (r = −0.69 and −0.54; p < 0.01, both), left (r = −0.56; p < 0.01) and right leg (r = −0.41; p < 0.05) AD, left leg AB (r = −0.48; p < 0.05) maximum isometric strength, left (r = −0.72; p < 0.01) and right (r = −0.64; p < 0.01) leg power output in leg press. In the case of the MAT test initiated on the right side first, the correlations were found between CMJ height (r = −0.46; p < 0.05), AD and AB maximum isometric strength of left (r = −0.58 and −0.84; p < 0.01, both) and right leg (r = −0.58 and −0.79; p < 0.01, both), and both legs power output in leg press (r = −0.66 for left and r = −0.59 for right; p < 0.01, both). The regression analyses showed that the prediction model of left leg press peak power, left leg AD maximum isometric strength, and CMJ height could explain up to 93% of the MAT test time initiated to the left first. The model, including left leg AB and AD maximum isometric strength, could explain up to 83% of the MAT test time initiated to the right side first. Findings from this study demonstrate that AB and AD maximum isometric muscle strength are highly related to MAT test performance, which is particularly important when the first turn is performed in the non−dominant direction in this test.

This study examined whether the 5-week pre-operative progressive exercise rehabilitation program with weekly monitoring contributed to a significantly lower muscle activity imbalance in the treatment group, both before and immediately after anterior cruciate ligament reconstruction (ACLR), as well as during the next 5 weeks in comparison to the control group. Twelve professional soccer players took part in the study (from among the top three Polish levels of competition) (age: 26 ± 5 years, body mass: 73 ± 7 kg, stature: 180 ± 6 cm, training experience: 15 ± 4 years). The participants were randomly assigned to the treatment group (n = 6) or to the control group (n = 6). Both groups performed the same pre- and post-operative progressive exercise rehabilitation program, while the rehabilitation of the treatment group was extended by supplementary body-weight functional stabilization training. The three-way repeated-measures ANOVA revealed a statistically significant interaction for muscle × group × time (p < 0.0001; F = 24.897; η2 = 0.806). The post-hoc analysis for the interaction effect of muscle × group × time indicated a significantly higher muscle activity imbalance for every measured muscle in the control group at any time point than in the treatment group (from p = 0.036 to p < 0.0001). The muscle activity imbalance was significantly higher from the 1st to 4th weeks than in the last week before surgery for quadriceps (p < 0.016 for all) and hamstrings (p < 0.001). However, in the case of gluteal muscles’ activity imbalance, it was significantly higher at every time point of the post-operative phase than in the last week before surgery (p < 0.001). The results of this study showed that the 5-week pre-operative rehabilitation program with weekly monitoring influenced outcomes of the post-operative phase. Nevertheless, performing both pre- and post-ACLR rehabilitation significantly reduced the muscle activity imbalance of lower limbs, but in the case of the quadriceps muscles, not to a sufficient level.

This study aimed to analyze acute changes in the muscle mechanical properties of the triceps brachii long head after bench press exercise performed at different external loads and with different intensities of effort along with power performance. Ten resistance-trained males (age: 27.7 ± 3.7 yr, body mass: 90.1 ± 17.1 kg, height: 184 ± 4 cm; experience in resistance training: 5.8 ± 2.6 yr, relative one-repetition maximum (1RM) in the bench press: 1.23 ± 0.22 kg/body mass) performed two different testing conditions in a randomized order. During the experimental session, participants performed four successive sets of two repetitions of the bench press exercise at: 50, 70, and 90% 1RM, respectively, followed by a set at 70% 1RM performed until failure, with a 4 min rest interval between each set. Immediately before and after each set, muscle mechanical properties of the dominant limb triceps brachii long head were assessed via a Myoton device. To determine fatigue, peak and average barbell velocity were measured at 70% 1RM and at 70% 1RM until failure (only first and second repetition). In the control condition, only muscle mechanical properties at the same time points after the warm-up were assessed. The intraclass correlation coefficients indicated “poor” to “excellent” reliability for decrement, relaxation time, and creep. Therefore, these variables were excluded from further analysis. Three-way ANOVAs (2 groups × 2 times × 4 loads) indicated a statistically significant group × time interaction for muscle tone (p = 0.008). Post hoc tests revealed a statistically significant increase in muscle tone after 70% 1RM (p = 0.034; ES = 0.32) and 90% 1RM (p = 0.011; ES = 0.56). No significant changes were found for stiffness. The t-tests indicated a significant decrease in peak (p = 0.001; ES = 1.02) and average barbell velocity (p = 0.008; ES = 0.8) during the first two repetitions of a set at 70% 1RM until failure in comparison to the set at 70% 1RM. The results indicate that low-volume, high-load resistance exercise immediately increases muscle tone but not stiffness. Despite no significant changes in the mechanical properties of the muscle being registered simultaneously with a decrease in barbell velocity, there was a trend of increased muscle tone. Therefore, further studies with larger samples are required to verify whether muscle tone could be a sensitive marker to detect acute muscle fatigue.

The aim of this study was to determine the effect of carbohydrate-protein supplementation with whey protein (CHO-PROw) after resistance training, and casein protein (PROc) before bedtime on the concentration of growth hormone (GH), insulin (I) and insulin-like growth factor (IGF-1), as well as serum creatine kinase (CK) activity. Twelve strength trained male subjects (age: 25.8 ± 4.7 years; training experience 6.1 ± 0.79 years; body mass 75.9 ± 2.7 kg; body height 171.8 ± 13.3 cm) were recruited for the study. They were randomly divided into an experimental group (group E, n = 6) and a control group (group C, n = 6). All study participants completed full barbell squats with a constant external load of 90% one-repetition maximum (1RM) and a volume of 12 sets. In each set three repetitions were performed with 3 min rest periods after each set. Immediately after the exercise protocol, the subjects from the experimental group received a carbohydrate-protein complex (CHO-PROw) with a dose of 0.5 g/kg of body mass, while before bedtime they ingested a protein supplement (PROc) consisting of 90% casein protein with a dose of 0.3 g/kg of body weight The results indicate that a ignificant increase in GH concentration occurred in the experimental group between the pre-exercise level and after 24 h of recovery (p

This study examined the effects of a short-term supplementary body-weight training program on changes in the muscle activity imbalance of the lower limbs during high-speed running in soccer players. Fifteen professional male soccer players took part in the study (age: 25 ± 5 years, body mass: 79.2 ± 10.8 kg, stature: 177 ± 10 cm, training experience: 12 ± 5 years). The evaluations of lower limb muscle activity imbalance via surface electromyography (sEMG) were performed twice (pre- and post-intervention), at a three-week interval. The sEMG was measured bilaterally from the area of quadriceps (Q), hamstrings (H), and gluteal muscles (G) during high-speed running at 18 km/h using sEMG shorts. Between measurements, the athletes performed the supplementary body-weight program of the lower limbs 4 times a week for 3 weeks. The training included six body-weight exercises performed unilaterally. The load progression included an additional set of each exercise in successive weeks of the experiment. The two-way repeated-measures ANOVA indicated a statistically significant main interaction for time × muscle (p = 0.006; F = 6.948; η2 = 0.332). The post-hoc analysis for the interaction effect of time × muscle showed a statistically significant decrease in muscle imbalance for the post-intervention compared to the pre-intervention for the H (p < 0.001; ES = 1.32), G (p = 0.002; ES = 0.92), and T (p < 0.001; ES = 1.54), but not for Q (p = 0.56; ES = 0.14). Moreover, there was a statistically significant greater imbalance between the H, G, and T muscles versus Q (p = 0.043, ES = 1.15; p = 0.006, ES = 1.57; p = 0.001, ES = 1.69, respectively) for the values recorded pre-intervention. Changes in muscle activity after 3 weeks of sports-specific movement patterns were statistically significant. For the gluteal (G) and hamstring (H), the imbalance between the limbs decreased significantly (p = 0.01). The imbalance in the quadriceps muscles (Q), with respect to each limb, did not decrease significantly (p = 0.82) following the training intervention. Conclusions: The results of this study indicate that in-season soccer training supplemented with a body-weight training program successfully decreases gluteal and hamstring imbalance between limbs after 3 weeks of training.

The main objective of this study was to evaluate the effects of different ischemic pressures applied during rest intervals on bar velocity during the bench press exercise. 10 resistance trained males (age = 23.2±2.7 years; body mass = 83.9±9 kg; body height = 181±5.2 cm; bench press 1 repetition maximum (1RM) = 125±16.4 kg; training experience = 5.4±3.4 years) participated in the study. During 4 experimental sessions, following a randomized crossover design, the subjects performed 5 sets of 3 repetitions of the bench press exercise with a load of 60% 1RM under conditions: with ischemia (50% or 80% of arterial occlusion pressure), with SHAM ischemia (20 mmHg) and without ischemia (control condition). For the ischemic conditions cuffs were applied before each set for 6.5 min and released 30 s before the start of the set as reperfusion (6.5 min ischemia + 0.5 min reperfusion). In the control condition, ischemia was not applied. The two-way repeated measures ANOVA showed no significant condition×set interaction for mean bar velocity (MV; p = 0.17) and peak bar velocity (PV; p = 0.66). There was also no main effect of condition for MV ( p = 0.58) and PV ( p = 0.61). The results indicate that ischemic or SHAM treatment (6.5 minutes ischemia or SHAM + 30 s reperfusion) does not affect mean and peak bar velocity during the bench press exercise regardless of the applied pressure.

The goal of the study was to determine the differences between volitional and maximal movement tempo during resistance exercise. Ten healthy men volunteered for the study (age = 26.4 ± 4.8 years; body mass = 93.8 ± 9.6 kg; barbell squat one-repetition maximum (1RM) = 175 ± 16.7 kg; bench press 1RM = 140.5 ± 26.8 kg). In a randomized order, the participants performed six sets of the barbell squat and the bench press exercise at progressive loads from 40% to 90%1RM (step by 10%) under two testing conditions: with volitional movement tempo or with maximal movement tempo. The three-way repeated measures ANOVA showed a statistically significant multi-interaction effect for time under tension (p

The main goal of the present study was to evaluate the acute effects of blood flow restriction (BFR) at 70% of full arterial occlusion pressure on strength-endurance performance during the bench press exercise. The study included 14 strength-trained male subjects (age = 25.6 ± 4.1 years; body mass = 81.7 ± 10.8 kg; bench press 1 repetition maximum (1RM) = 130.0 ± 22.1 kg), experienced in resistance training (3.9 ± 2.4 years). During the experimental sessions in a randomized crossover design, the subjects performed three sets of the bench press at 80% 1RM performed to failure with two different conditions: without BFR (CON); and with BFR (BFR). Friedman’s test showed significant differences between BFR and CON conditions for the number of repetitions performed (p < 0.001); for peak bar velocity (p < 0.001) and for mean bar velocity (p < 0.001). The pairwise comparisons showed a significant decrease for peak bar velocity and mean bar velocity in individual Set 1 for BFR when compared to CON conditions (p = 0.01 for both). The two-way repeated measures ANOVA showed a significant main effect for the time under tension (p = 0.02). A post-hoc comparisons for the main effect showed a significant increase in time under tension for BFR when compared to CON (p = 0.02). The results of the presented study indicate that BFR used during strength-endurance exercise generally does not decrease the level of endurance performance, while it causes a drop in bar velocity

Post-activation performance enhancement remains a topic of debate in sport science. The purpose of this study was to examine the effects of lower-body plyometric conditioning activity (CA) with a self-selected intra-complex rest interval on upper and lower-body volleyball specific performance. Eleven resistance-trained female volleyball players participated in the study (age: 20 ± 2 years; body mass: 67.8 ± 4.4 kg; height: 178 ± 6 cm; half back squat one-repetition maximum: 78.6 ± 10.2 kg; experience in resistance training: 5.5 ± 2.1 years and in volleyball training: 10 ± 2.3 years). Each participant performed a plyometric CA followed by two different sport-specific tests: an attack jump and a standing spike attack. The changes in jump height (JH), relative mean power output (MP) and ball velocity (BV) were analyzed before and after the CA with self-selected rest intervals. The applied plyometric CA with self-selected intra-complex rest intervals led to an insignificant decline in JH (p = 0.594; effect size [ES]: −0.27) and MP (p = 0.328; ES: −0.46) obtained during the attack jump as well as a significant decline in BV (p = 0.029; ES: −0.72) during the standing spike attack. This study showed that a plyometric CA with self-selected intra-complex rest intervals failed to elicit localized and non-localized PAPE effect in a group of sub-elite volleyball players.