The present study aimed to evaluate the effects of ischemic intra-conditioning applied during rest intervals on 30 m sprint performance. Thirty-four trained male (n = 12) and female (n = 22) track and field and rugby athletes volunteered to participate in the study (age = 19.6 ± 4 years; training experience = 5.3 ± 1.9 years). In a randomized and counterbalanced order, participants performed six sets of 30 m sprints under three different testing conditions: without ischemic intra-conditioning, and with ischemic intra-conditioning at 60% or 80% arterial occlusion pressure applied bilaterally before the first trial of the sprint and during the rest periods between all sprint trials. During experimental sessions, subjects perform 6 × 30 m sprints with a 7 min rest interval between attempts. The cuffs were applied following a 1 min rest period and lasted for 5 min before being released at the 6th minute to allow for reperfusion (1 min + 5 min ischemic intra-conditioning + 1 min reperfusion). The two-way repeated measures ANOVA did not show statistically significant condition × set interaction for time of the sprint (p = 0.06; η² = 0.05). There was also no main effect of ischemic intra-conditioning for any condition (p = 0.190; η² = 0.05). This study indicates that ischemic intra-conditioning did not enhance the performance of 30 m sprints performed by athletes. However, ischemic intra-conditioning did not decrease performance either.

Introduction: The main goal of this study was to investigate the effects of a single cycle of ischemia applied before the bench press exercise on acute bar velocity changes. Materials and Methods: Twelve physically active males participated in the study. The experiment followed a randomized, cross-over design under two testing conditions. The experimental condition involved the application of a single cycle of ischemia (5 minutes; 80% arterial occlusion pressure [AOP]) before the first set of bench press exercise (2 sets at 60% 1RM). The control condition did not use ischemia. The peak and mean bar velocities were measured using a linear position transducer. Results: Two-way repeated measures ANOVA revealed no statistically significant differences in the peak or mean bar velocity between the ischemia and control conditions both during the first and the second set of the bench press exercise. Conclusions: The results of this study indicate that a single cycle of ischemia applied before the bench press exercise did not influence changes in peak or mean bar velocity.

The study aimed to evaluate the impact of blood flow restriction (BFR) used only before sets of isokinetic knee extensions on torque and muscle activity of the Rectus Femoris muscle. Twenty healthy physically active males (age = 22.7 ± 6.7 years; body mass = 83.0 ± 15.9 kg; body height = 180.8 ± 8.3 cm) performed three experimental sessions in a random crossover design (BFR - with blood flow restriction; control - without BFR, Sham). In the BFR and Sham conditions cuffs were applied for 5 min and released 1 min prior to each set of isokinetic knee extensions. The pressure of the cuffs was 80% AOP (arterial occlusion pressure) for BFR conditions and 20 mmHg for Sham conditions. For Control conditions no restriction was applied. Experimental sessions consisted of 5 sets of 3 isokinetic knee extensions (180°/s) with 6.5-min rest intervals between sets. The repetitions were performed with maximal effort. During the concentric phase of the exercise peak torques and peak electromyographic activity of Rectus Femoris muscle were gathered. The eccentric phase was passive. The two-way repeated measures ANOVA did not show statistically significant condition × set interaction for peak torque and muscle activity. There was also no main effect of condition as well as no main effect of set for peak torque and muscle activity. The results of this study indicate that BFR intra-conditioning (5 min; 80% AOP; 1 min reperfusion) did not significantly affect strength performance or Rectus Femoris EMG activity. However, the lack of performance decline suggests it does not impair neuromuscular output, which may be beneficial in high-load training with long rest intervals. Previous research shows that BFR may induce adaptive changes not examined here. Further studies should explore these adaptations and the effects of varying BFR parameters, intensities, and work to rest ratios.

Study aim: Circadian rhythms influence numerous physiological processes, including vascular regulation and skin microcirculation. However, evidence regarding diurnal variability in post-occlusive reactive hyperemia (PORH) parameters remains limited. The aim of this study was to investigate the effect of time of day on skin microcirculatory responses assessed using laser Doppler flowmetry during a PORH test in healthy adults. Material and methods: Thirty healthy volunteers (15 women and 15 men) participated in the study. Skin microcirculation was assessed twice on the same day using laser Doppler flowmetry: in the morning (08:00–10:00) and in the evening (18:00–20:00). The analyzed parameters included resting flow (RF), biological zero (BZ), peak perfusion (PP), time to peak (TTP), and recovery time (TTR). A standardized occlusion protocol (100% arterial occlusion pressure for 3 min) was applied, followed by 4 min of post-occlusive monitoring. Data distribution was assessed using the Shapiro–Wilk test. Due to non-normal distribution, paired comparisons were performed using the Wilcoxon signed-rank test. Statistical significance was set at p < 0.05. Results: Resting flow was significantly higher in the evening compared with the morning (p = 0.038), indicating moderate diurnal variability in basal skin blood flow. No significant differences were observed for BZ, PP, TTP, or TTR (p > 0.05). Conclusions: Time of day influences resting skin blood flow but does not affect PORH parameters in healthy adults. These findings suggest that basal microvascular tone shows diurnal variability, whereas the reactive microcirculatory response remains stable. Therefore, measurement timing should be considered when interpreting resting microcirculatory assessments.