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Background: This study aimed to examine the effects of two complex training sequences on acute post-activation potentiation enhancement in countermovement jump (CMJ) performance. Methods: Twenty-two recreationally active males performed CMJ before and 1, 4, and 8 min after two sequences of complex training conducted in reverse order, consisting of a heavy load comprising three sets of squats with a 15% velocity-loss and three sets of maximal CMJ with a 10% height-loss for the low load. Results: No significant differences (p > 0.05) were observed in the interaction time × condition in CMJ variables. At the individual level, 23, 9, and 32% of participants improved CMJ performance in the high loads–low loads sequence at 1, 4, and 8 min compared to the baseline, respectively. In comparison, 14%, 23%, and 27% of participants improved CMJ performance in the light loads–high loads sequence. Eight participants in each sequence did not improve CMJ performance at any time, although these participants were not the same in both sequences. Conclusions: Stronger athletes (1.65 ± 0.28 relative force) seemed to benefit more from the high loads-low loads sequence. In conclusion, there were no non-responders, as all the participants improved at some time point. The strength levels may be one of the moderating variables.

Objective: This study evaluated the effects of advanced footwear technology (AFT) spikes on running performance measures, spatiotemporal variables, and perceptive parameters on different surfaces (track and grass). Methods: Twenty-seven male trained runners were recruited for this study. In Experiment 1, participants performed 12 × 200 m at a self-perceived 3000 m running pace with a recovery of 5 min. Performance (time in each repetition), spatiotemporal, and perceptive parameters were measured. In Experiment 2, participants performed 8 × 5 min at 4.44 m/s while energy cost of running (W/kg), spatiotemporal, and perceptive parameters were measured. In both experiments the surface was randomized and mirror order between spike conditions (Polyether Block Amide (PEBA) and PEBA + Plate) was used. Results: Experiment 1: Runners were faster on the track (p = 0.002) and using PEBA + Plate spike (p = 0.049). Experiment 2: Running on grass increased energy cost (p = 0.03) and heart rate (p < 0.001) regardless of the spike used, while PEBA + Plate spike reduced respiratory exchange ratio (RER) (p = 0.041). Step frequency was different across surfaces (p < 0.001) and spikes (p = 0.002), with increased performance and comfort perceived with PEBA + Plate spikes (p < 0.001; p = 0.049). Conclusions: Running on the track surface with PEBA + Plate spikes enhanced auto-perceived 3000 m running performance, showed lower RER, and improved auto-perceptive comfort and performance. Running on grass surfaces increased energy cost and heart rate without differences between spike conditions.

Abstract The NIKE Vaporfly shoe was introduced in May 2017 as part of the original #Breaking2 Project (an event aimed to run the first marathon under 2 h). This new advanced shoe technology (NAST) changed the footwear design conception. The aim of this study was (i) to analyse the effect of NAST in men’s marathon performance, (ii) to analyse whether the changes in the environmental constraints (temperature and wind) and orography of the marathons, age and birthplace of the runners has changed from 2015 to 2019 and (iii) to analyse the impact of NAST on the historical 50 best performances. Data from top-100 men's marathon performances were collected in that timeframe. The shoes used by the athletes were identified (in 91.8% of the cases) by publicly available photographs. External and environmental conditions of each marathon and age and birthplace of the runners were also analysed. Marathon performances improved from 2017 onwards between 0.75 and 1.50% compared to 2015 and 2016 (p

PurposeThe aim of this study was to assess the effects of adding shoe mass on running economy (RE), gait characteristics, neuromuscular variables and performance in a group of trained runners.MethodsEleven trained runners (6 men and 5 women) completed four evaluation sessions separated by at least 7 days. The first session consisted of a maximal incremental test where the second ventilatory threshold (VT2) and the speed associated to the VO2max (vVO2max) were calculated. In the next sessions, RE at 75, 85, and 95% of the VT2 and the time to exhaustion (TTE) at vVO2max were assessed in three different shoe mass conditions (control, +50 g and +100 g) in a randomized, counterbalanced crossover design. Biomechanical and neuromuscular variables, blood lactate and energy expenditure were measured during the TTE test.ResultsRE worsened with the increment of shoe mass (Control vs. 100 g) at 85% (7.40%, 4.409 ± 0.29 and 4.735 ± 0.27 kJ⋅kg−1⋅km−1, p = 0.021) and 95% (10.21%, 4.298 ± 0.24 and 4.737 ± 0.45 kJ⋅kg−1⋅km−1, p = 0.005) of VT2. HR significantly increased with the addition of mass (50 g) at 75% of VT2 (p = 0.01) and at 75, 85, and 95% of VT2 (p = 0.035, 0.03, and 0.03, respectively) with the addition of 100 g. TTE was significantly longer (∼22%, ∼42 s, p = 0.002, ES = 0.149) in the Control condition vs. 100 g condition, but not between Control vs. 50 g (∼24 s, p = 0.094, ES = 0.068).ConclusionOverall, our findings suggest that adding 100 g per shoe impairs running economy and performance in trained runners without changes in gait characteristics or neuromuscular variables. These findings further support the use of light footwear to optimize running performance.

Speed climbing will be a new discipline in Paris 2024. The physical requirements of speed climbing are different from the other climbing modalities due to the short event time requiring higher level of strength and power. These parameters have been measured through the Force Velocity (F-V) profile in different climbing disciplines. However, there are no known results evaluating different speed climbing abilities to establish whether F-V relationship is a determining factor between performance levels. The purpose of this study was to evaluate the upper and lower limbs F-V profile in different speed climbing abilities considering sex. Twenty six speed climbers were divided into two groups based on their level of performance: international level (men n = 7 and women n = 2) and national level (men n = 8 and women n = 7). Participants performed pull-ups and squat incremental tests and F-V profile variables [Maximum theorical values of force (F 0 ), velocity (V 0 ) and power (P max )], one-repetition maximum value (1RM) and %1RM where peak power was expressed were collected using a linear encoder. There were significant differences in F 0 , relative force, %1RM where peak power was expressed, and 1RM in pull-ups ( p < 0.05) between groups. However, there were not significant differences between groups in squat variables. No significant sex differences were found in any variable. There were moderate-strong correlations between running time and 1RM (pull-ups and squat), F 0 and FV-slope (pull-ups) ( p < 0.05) analyzed in the whole group. In conclusion, F 0 and 1RM in pull-ups were significantly higher in international climbers. Therefore, national climbers should focus their training on improving force by training with heavy loads. Additionally, squat F-V profile variables do not seem to be as important as in the pull-up for performance.

The aim of this study was to analyze the acute effects of high vs low-intensity cycling efforts, combined with plyometrics, on vertical jump performance. Twenty-four physically active men (mean ±SD: 23 ± 2 years, 72.1 ± 10.1 kg, 1.73 ± 0.07 m) were randomly divided into two groups: experimental group (EXP, n = 16) and control group (CON, n = 8). EXP competed 2 experimental trials in a random order: (a) short high-intensity interval exercise (HI + Plyo) [5 × 10 s of cycling (“all-out”)/50 s active rest] or (b) low-intensity continuous exercise (LO + Plyo) [5 min of cycling at 75% of the HRmax)], along with 3 × 10 plyometric bounds (drop jumps)/1 min rest between sets. CON used a preconditioning activity of 13 min of low intensity cycling at ~60% of HRmax. Both EXP interventions significantly increased (p ≤ 0.05) the countermovement jump (CMJ) height at 1 min, 3 min, 6 min and 9 min compared to baseline, while the CON remained unchanged. There were no significant differences in CMJ performance enhancement between HI + Plyo (largest 11.2% at 9 min) and LO + Plyo (largest 15.0% at 3 min) at any time-point, suggesting that the plyometric component may be most important, with HR recovery taking slightly longer following HI + Plyo. The findings suggest that CMJ performance can be enhanced following high or low-intensity cycling combined with plyometric preconditioning activities in active males, the optimum recovery period likely to be individual-specific.

Background: Quantifying the potential benefits of advanced footwear technology (AFT) track shoes (i.e., “spikes”) in middle-distance events is challenging, because repeated maximal effort trials (as in sprinting) or aerobic running economy trials (as in long-distance running) are not feasible. Methods: We introduce a novel approach to assess the benefits of AFT spikes, consisting of a series of 200-m runs at self-perceived middle-distance race pace with 10 min recovery, and conduct 4 experiments to evaluate its validity, sensitivity, reproducibility, and utility. Results: In Experiment 1, participants ran 1.2% slower in spikes with 200 g added mass vs. control spikes, which is exactly equal to the known effects of shoe mass on running performance. In Experiment 2, participants ran significantly faster in AFT prototype spikes vs. traditional spikes. In Experiment 3, we compared 2 other AFT prototype spikes against traditional spikes on 3 separate days. Group-level results were consistent across days, but our data indicates that at least 2 separate sessions are needed to evaluate individual responses. In Experiment 4, participants ran significantly faster in 2 AFT spike models vs. traditional spikes (2.1% and 1.6%). Speed was similar between a third AFT spike model and the traditional spikes. These speed results were mirrored by changes in step length as participants took significantly longer steps in the 2 faster AFT spike models (2.3% and 1.9%), while step length was similar between the other spikes. Conclusion: Our novel, interval-based approach is a valid and reliable method for quantifying differences between spikes at middle-distance running intensity.

Background: The main objectives of this study were to analyze the effect of early specialization in swimming and to observe the general patterns of success of two different sport specialization models [Spanish (SPA) and United States of American (USA) swimmers] participating in World Championships (WCs) and Olympic Games (OGs) between the years 2006 and 2021 of all swimming strokes and distances. Methods: Descriptive analyses and contingency tables were examined for all the variables. Explanatory models of the z scores were estimated from age depending on the events’ distances and strokes. Quadratic regression models were developed to capture the behavior of the variable time with parabolic functions, and the significance of the global model and the predictor variables (age) were also evaluated. In addition, the optimal age (peak performance) as well as the curvature of the model were analyzed. These models were compared between SPA and USA swimmers. Results: The results showed that the main differences in the patterns to success between SPA and USA were the earlier participation of USA swimmers in high-level competitions, as well as the greater number of participants for all the strokes, events, genders, and competitions. Age peak performance in short distances was lower for Spanish swimmers, obtaining the opposite situation for long distances. Conclusions: Being a finalist in junior WCs did not influence success in the finals of the senior WCs and OGs. Main differences in general patterns of success between SPA and USA showed younger swimmers participating in short-distance events, backstroke, and butterfly for USA swimmers and older swimmers taking part in butterfly and short-distance events for SPA.