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Purpose: Both aerobic fitness and muscular power have been reported as crucial for elite alpine ski racing1. To date, aerobic fitness has been mainly investigated in skiers using incremental cycling step test, while muscular power by the mean of jump testing such as countermovement jump (CMJ)1. However, no research investigated the relationship between these two fundamental systems. Thus, our purpose was to study the relationship between the maximal cycling workload (MCW) and CMJ- derived metrics. Methods: Sixteen young alpine skiers (gender: 7 F / 9 M; age: 16.7 ± 1.3 years; BMI: 22.8 ± 1.9 kgm-2) performed 2 CMJ trials using an Optojump system2. First, the jump height (CMJH) was computed from the highest trial, as well as the jump peak mechanical power (CMJP) using the Johnson & Bahamonde formula3, including CMJH and participants’ height and weight. Then MCW was determined through an incremental maximal cycling test performed at 80 rpm. After a 3-min warm-up (at 50 W for females and 75 W for males), the workload increased every minute with 15 W steps for females and 25 W for males until exhaustion. MCW was registered as the workload of the last step completed before exhaustion. A stepwise regression model tested the relationship between MCW and CMJ-derived metrics. CMJH and CMJP were entered as continuous predictors, with a threshold to enter and remove terms equal to 0.15. The significance level was set to a = 0.05. Results: Both CMJH (36.2 ± 9.1 cm) and CMJP (2929 ± 1006 W) were included in the model (R2 = 84.9%) and resulted significantly positively correlated with MCW (282 ± 81 W) (F = 5.9, p = 0.030; and F = 36.5, p\0.001 respectively). Follow-up individual linear regression models confirmed the relationships (CMJH: R2 = 45.5%, F = 10.4, p = 0.006; CMJP: R2 = 78.1%, F = 49.6, p\0.001). Conclusions: The presented results demonstrated that both CMJ metrics were positively correlated with MCW, with a strengthened relationship for CMJP, thus adjusting CMJ per

Background: The etiology of Anterior Cruciate Ligament (ACL) injury in women football results from the interaction of several extrinsic and intrinsic risk factors. Extrinsic factors change dynamically, also due to fatigue. However, existing biomechanical findings concerning the impact of fatigue on the risk of ACL injuries remains inconsistent. We hypothesized that fatigue induced by acute workload in short and intense game periods, might in either of two ways: by pushing lower limbs mechanics toward a pattern close to injury mechanism, or alternatively by inducing opposed protective compensatory adjustments. Aim: In this study, we aimed at assessing the extent to which fatigue impact on joints kinematics and kinetics while performing repeated changes of direction (CoDs) in the light of the ACL risk factors. Methods: This was an observational, cross-sectional associative study. Twenty female players (age: 20–31 years, 1st–2nd Italian division) performed a continuous shuttle run test (5-m) involving repeated 180°-CoDs until exhaustion. During the whole test, 3D kinematics and ground reaction forces were used to compute lower limb joints angles and internal moments. Measures of exercise internal load were: peak post-exercise blood lactate concentration, heart rate (HR) and perceived exertion. Continuous linear correlations between kinematics/kinetics waveforms (during the ground contact phase of the pivoting limb) and the number of consecutive CoD were computed during the exercise using a Statistical Parametric Mapping (SPM) approach. Results: The test lasted 153 ± 72 s, with a rate of 14 ± 2 CoDs/min. Participants reached 95% of maximum HR and a peak lactate concentration of 11.2 ± 2.8 mmol/L. Exercise duration was inversely related to lactate concentration (r = −0.517, p < 0.01), while neither%HRmax nor [La–]b nor RPE were correlated with test duration before exhaustion (p > 0.05). Alterations in lower limb kinematics were found in 100%, and in lower limb kine

© 2020, CIC Edizioni Internazionali s.r.l.. All rights reserved. Background. Kitesurfing is one of the world’s fastest growing Olympic aquatic sports. However, previous scientific literature on this sport has mainly focused on acute inju-ries. The aim of this study was, therefore, to capture a picture of the burden of overuse injuries in kitesurfing. Methods. Active kite-surfers regularly completed an online questionnaire, describing the health of their shoulders, lower back and knees as well as any injury related symp-toms. Results. Forty-three participants completed a total of 304 questionnaires, covering a total period of 2,096 distinct person-days. Person-days of reduced participation related to shoulder, lower back and knee problems were 8 %, 3% and 8% of the total respectively. Performance was affected related to shoulder, lower back and knee problems in 11%, 22% and 16% of person-days respectively. Conclusions. Overuse injuries emerged as an important predictor of reduced partici-pation, decreased performance and discomfort in kitesurfing. The prospective survey method captured a picture of overuse injuries in kitesurfing not previously described.

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