(1) Purpose: This study aimed to explore the time duration of post-activation performance enhancement (PAPE) in elite male sprinters with different strength levels. (2) Methods: Thirteen elite male sprinters were divided into a strong group (relative strength: 1RM squat normalized by body mass of ≥2.5; n = 6) and a weak group (relative strength of <2.5; n = 7). All sprinters performed one static squat jump (SSJ) at baseline and 15 s, 3 min, 6 min, 9 min, and 12 min following an exercise protocol including three reps of a 90% 1RM back squat. Two force plates were used to determine the vertical jump height, the impulse output, and the power output for all SSJs. (3) Results: Significant improvements in vertical jump height and peak impulse were observed (p < 0.05) at 3, 6, and 9 min, without significant between-group differences. The peak power had a significant increase in 3 min (p < 0.01) and 6 min (p < 0.05), with also no significant difference between-group differences. Moreover, the stronger subjects induced a greater PAPE effect than the weaker counterparts at 3, 6, and 9 min after the intervention. The maximal benefit following the intervention occurred at 6 min and 3 min after the intervention in the stronger and weaker subjects, respectively. (4) Conclusions: The findings indicated that three reps of a 90% 1RM back squat augmented the subsequent explosive movement (SSJ) for 3–9 min in elite male sprinters, especially in stronger sprinters.

This study aimed to determine the optimal functional movement screen (FMS) cut score for assessing the risk of sport injury, and to investigate the correlations between functional movement quality and sprint and jump performance. Twenty-four (N = 24) athletes performed all tests in one day at 10–30 min intervals, and the FMS test was performed first, without a warm-up session. After a standard warm-up, athletes then completed the Y-balance Test (YBT), sprint, counter-movement jump (CMJ), and standing long jump (SLJ), in turn. For each test, the best of three attempts was recorded for further analysis. A receiver operating characteristic (ROC) curve and area-under-the-curve (AUC) were used to determine the optimal FMS cut score for assessing the risk of sport injuries, and Spearman’s rank correlation analysis was used to quantify associations between functional movement scores and athletic performance. The average FMS score was 16.2 and the optimal FMS cut score for assessing the risk of sport injuries was 14.5. There were moderate relationships between total FMS score and 10–20 m sprint time (r = −0.46, p < 0.05), between In-line Lunge and 0–20 m sprint time (r = −0.47, p < 0.05), between Shoulder Mobility and 0–10 m sprint time (r = −0.48, p < 0.05), and between Trunk-stability Push-up and 10–20 m sprint time (r = −0.47, p < 0.05). Moreover, Hurdle Step score was largely correlated with 0–10 m time (r = −0.51, p < 0.05). For Y-balance, moderate correlations were observed between CMJ height and anterior asymmetry score (r = −0.47, p < 0.05) and posteromedial asymmetry score (r = −0.44, p < 0.05). However, there were no significant associations between YBT performance (asymmetric in three directions and composite score) and sprint performance (p > 0.05). Taken together, the results indicate that a FMS score of 14 is not a gold standard for assessing the risk of injury in all populations; we recommend that the FMS cut score of 14.5 should be the optimal score for assessing risk of injury in young female elite soccer players. Moreover, the FMS and YBT were introduced to assess the quality of functional movements, and they cannot be used to assess sprint and jump performance. Practitioners can use components of the FMS that have similar characteristics to specific sports to assess athletic performance.

Objectives: This review aimed to clarify the associations between COD performance and asymmetries on horizontal jumping, vertical jumping, and strength. Methods: Three databases, including PubMed, Web of Science, and MEDLINE(EBSCOhost) were used to perform a systematic literature search. The search was up to 13 March 2022 and was limited to the literature in the English language and on the human species. Studies included reported exact measurement tools and correlation coefficients and studies in which participants aged >14 years were included. Moreover, studies that were not peer-reviewed and those that did not report an asymmetry index were excluded, as were studies for which the full text was not available. The modified Downs and Black Quality Index tool was used to evaluate the quality of the studies. Results: The systematic literature identified 1151 studies, but only 12 studies were included in this review. A total of 354 participants, ranging from 15 to 23 years of age, were recruited for these studies. The methodological quality score ranged from 6 to 8, with an average of 7.25. The associations between COD performance and vertical jump height, horizontal jump distance, and lower-limb strength asymmetries were examined in 11, 5, and 2 studies, respectively. Six studies reported that vertical jump height asymmetries scores can significantly reduce COD performance, while significant associations between COD performance and horizontal jump distance asymmetries and strength asymmetries were only observed in one study each. Specifically, four studies explored the relationships between CMJ height asymmetries scores and COD performance, and all reported significant associations between them. The main limitations of this review were that it did not consider the sports in which the participants were involved. Conclusions: This study suggests that drop jump height and eccentric knee strength asymmetries can reduce COD performance. Moreover, low horizontal jump asymmetries may not influence COD performance. Further research needs to determine whether the minimal threshold of horizontal jump asymmetries would not affect COD performance.

Objective This study compared the effects of two high-intensity interval training programs, one program based on speed endurance maintenance training(SEMT)vs. one program based on repeated sprint training (RST) on the anaerobic performance of Chinese national alpine skiers. Methods Eighteen Chinese national alpine skiers (age:19.8 ± 1.9 years old) were randomly assigned into two groups. One used RST (6 repetitions involving 10s sprint, 5s rest in each repetition, 5 sets, 180s recovery between each set), another used SEMT (5 sets, 60s sprint,180s recovery in each set). The training intervention lasted four weeks, 48 hours before (baseline) and after the intervention, the participants were assessed in the countermovement jump test (CMJ), 90s lateral box jump test, and 90s Wingate test. Both training interventions consisted of 12 sessions (3 sessions per week). Results The CMJ changed 2.77% (p = 0.017; d = 0.995) for the RST group, though no significance was found 0.73% (p = 0.424; d = 0.281) for the SEMT group. The 90s lateral box jump changes occurred both in the RST and SEMT group and amounted to 9.21% (p = 0.004; d = 1.347) and 7.52% (p = 0.000; d = 2.089) respectively. The 90s Wingate RPP changed 2.35% (p = 0.003; d = 1.384) for the RST group, though no significance was found − 0.09% (p = 0.972; d = 0.012) for the SEMT group. The 90s Wingate RMP changed 3.91% (p = 0.017; d = 1.002) for the SEMT group, though no significance was found 1.49% (p = 0.056; d = 0.746) for the RST group. The 90s Wingate FI changed − 3.38% (p = 0.001; d = 1.622) for the SEMT group, though no significance was found 0.08% (p = 0.943; d = 0.025) for the RST group. Significant differences were found between the groups in the changing amplitude for 90s Wingate RPP (p = 0.037; d = 1.073) and 90s Wingate FI (p = 0.020; d = 1.214). Conclusion (1) Both types of training have notable gains in improving anaerobic capacity. (2) RST is more effective to improve athletes' anaerobic explosive power. (3) SEMT is more effective in improving the anaerobic endurance.

Yang, Z, Peng, F, Lin, J, Zeng, Y, Su, Y, Shi, Y, and Li, W. Acute physiological and perceptual responses to decreasing-distance versus constant-distance HIIT in elite male speed skaters. J Strength Cond Res XX(X): 000–000, 2026—This study investigated the acute effects of a decreasing-distance high-intensity interval training (D-HIIT) strategy vs. a constant-distance HIIT (C-HIIT) protocol on endurance performance, physiological responses, and rating of perceived exertion (RPE) in elite speed skaters. Eighteen Tier-4 male speed skaters were randomized into D-HIIT (1,600, 1,200, 1,200, and 800 m) or C-HIIT (4 × 1,200 m) groups, matched for total distance (4,800 m). Velocity drop rate (VDR), heart rate (HR), blood lactate (BLa), and RPE were monitored. D-HIIT resulted in a significantly shorter total time (381.89 ± 3.55 seconds vs. 393.11 ± 2.93 seconds, p < 0.001) and lower VDR (2.10 ± 0.27% vs. 3.72 ± 0.24%; p < 0.001). D-HIIT also elicited higher peak BLa in the final bout (11.81 ± 0.29 vs. 9.31 ± 0.29 mmol·L ⁻¹ , p < 0.001), while terminal RPE was lower than that in C-HIIT (17.22 ± 0.67 vs. 18.22 ± 1.13, p < 0.05). D-HIIT was associated with faster completion, lower velocity drop, higher HR and BLa responses, and lower terminal RPE than C-HIIT under matched external distance. Because RPE did not show a significant Group × Bout interaction, the perceptual findings should be interpreted cautiously. Decreasing-distance high-intensity interval training may be considered as an acute session format for imposing a high physiological stimulus while maintaining manageable perceived exertion, but its mechanisms and long-term training effects require further investigation.