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The aim of the present study was to analyse differences in acceleration and movement variability caused by adding whole-body vibration (WBV) and an implement (stick) while performing a slide-board (SB) skating exercise. A total of 10 professional ice-hockey players (age 20.4 ± 2.07 years) participated in the study. Participants performed 30 s of lateral sliding on a slide vibration board (SVB). Four conditions were analysed: no vibration and no stick (NVNS), no vibration with a stick (NVS), vibration without a stick (VNS) and vibration with a stick (VS). Peak acceleration, mean acceleration and movement variability (MV) were analysed in the dominant and non-dominant legs in each condition. Peak acceleration was higher in the non-dominant leg (p < 0.01). However, MV was higher in the dominant leg (p < 0.01). Regarding differences between conditions, mean acceleration was higher in VNS and VS than in NVS (p < 0.05). Regarding MV (sample entropy), there were differences in NVNS compared to VNS and VS (p < 0.01) and in NVS compared to VNS and VS (p < 0.01), with the values being superior in VNS and VS. The addition of WBV during an SB skating exercise results in an increase in MV and mean acceleration. The dominant leg shows greater MV regardless of the addition of vibration and a stick during sliding on an SVB. [ABSTRACT FROM AUTHOR]

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The purpose of this study was to determine the feasibility of a purpose-designed vibratory bar (VB) as a potential vibration training device and thereafter to assess its effects on upper-body muscles' electromyographic (EMG) activity during vibration. During session 1, 16 physically active males held the VB during the bench press exercise in an isometric extended position (EP) in the following vibration conditions selected in the inverter ([sub.i]): no vibration (0), 20, 30, 40, and 50 [Hz.sub.i]. Maximal acceleration ([Acc.sub.max]), frequency (Freq), and peak-to-peak amplitude ([Amp.sub.p-p]) obtained at the center (C) and at the end (E) of the VB were assessed using an accelerometer. During session 2, EMGrms of the triceps, deltoid, and pectoralis major were recorded in EP and isometric flexion position (FP) at 0, 25, and 45 [Hz.sub.i]. The [Acc.sub.max], Freq, and [Amp.sub.p-p] values ranged from 37.4 to 96.4 m x [s.sup.-2], 18.5 to 30.8 Hz, and 4.6 to 6.1 mm, respectively. The accelerometer's position had a significant effect on the [Acc.sub.max] and [Amp.sub.p-p]. All Freq obtained at C and E were different (p < 0.001) to the [Freq.sub.i]. An increase (p < 0.05) in EMGrms was observed in both vibration conditions compared with 0 [Hz.sub.i], except during 25[Hz.sub.i] for deltoid and pectoralis muscle in FP. Although no significant differences were found in any of the muscles between 45 [Hz.sub.i] and 25[Hz.sub.i], the highest EMGrms was elicited at 45[Hz.sub.i]. Although the registered VBs' parameters seem appropriate for vibration training, the frequency in the FP should be higher than 25 [Hz.sub.i] to induce significant increases in EMGrms in deltoid and pectoralis muscles. The use of a vibratory bar may be a suitable system to simultaneously stimulate upper-body muscles. KEY WORDS vibration exercise, neuromuscular, posture, strength, reflex

Lifting velocity may have a great impact on strength training-induced adaptations. The purpose of this study was to validate a method including a metronome and a measurement tape as inexpensive tools for the estimation of mean lifting velocity during the bench press exercise. Fifteen subjects participated in this study. After determining their one repetition maximum (1RM) load, we estimated the maximum metronome rhythm (R) that each subject could maintain in the concentric phase for loads of 40 and 60% of 1 RM. To estimate R, the 3 repetitions with highest concentric power, as measured by means of a linear encoder, were selected, and their average duration was calculated and converted to lifting rhythm in beats per minute (bpm) for each subject. The range of motion was measured using a regular tape and kept constant during all exercises. Subjects were instructed to begin with the barbell at arm lengths and lower it in correspondence with the metronome beep. They subsequently performed 5 repetitions at 3 different rhythms relative to R (50, 70, and 90% R) for each training load (40 and 60% of 1RM). A linear encoder was attached to the bar and used as a criterion to measure the vertical displacement over time. For each rhythm, the mean velocity was calculated with the metronome (time) and the reference distance and compared with that recorded by the linear encoder. The SEM for velocity between both testing methods ranged from 0.02 to 0.05 m-s-1 (coefficient of variation, 4.0-6.4%; Pearson's correlation, 0.8-0.95). The present results showed that the use of a metronome and a measurement tape may be a valid method to estimate the mean velocity of execution during the bench press exercise. This simple method could help coaches and athletes achieve their strength training goals, which are partly determined by lifting velocity. KEY WORDS coefficient of variation, rhythm, strength training assessment

Purpose: To analyze the effects of 2 different eccentric-overload training (EOT) programs, using a rotational conical pulley, on functional performance in team-sport players. A traditional movement paradigm (ie, squat) including several sets of 1 bilateral and vertical movement was compared with a novel paradigm including a different exercise in each set of unilateral and multi-directional movements. Methods: Forty-eight amateur or semiprofessional team-sport players were randomly assigned to an EOT program including either the same bilateral vertical (CBV, n = 24) movement (squat) or different unilateral multidirectional (VUMD, n = 24) movements. Training programs consisted of 6 sets of 1 exercise (CBV) or 1 set of 6 exercises (VUMD) x 6-10 repetitions with 3 min of passive recovery between sets and exercises, biweekly for 8 wk. Functional-performance assessment included several change-of-direction (COD) tests, a 25-m linear-sprint test, unilateral multidirectional jumping tests (ie, lateral, horizontal, and vertical), and a bilateral vertical-jump test. Results: Within-group analysis showed substantial improvements in all tests in both groups, with VUMD showing more robust adaptations in pooled COD tests and lateral/horizontal jumping, whereas the opposite occurred in CBV respecting linear sprinting and vertical jumping. Between-groups analyses showed substantially better results in lateral jumps (ES = 0.21), left-leg horizontal jump (ES = 0.35), and 10-m COD with right leg (ES = 0.42) in VUMD than in CBV. In contrast, left-leg countermovement jump (ES = 0.26) was possibly better in CBV than in VUMD. Conclusions: Eight weeks of EOT induced substantial improvements in functional-performance tests, although the force-vector application may play a key role to develop different and specific functional adaptations. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the immediate effects of cold-water immersion (CWI) and hot-water immersion (HWI) versus passive resting after a fatigue-induced bout of exercise on the muscle contractile properties of the Vastus Medialis (VM). We conducted a randomised cross-over study involving 28 healthy active men where muscle contractile properties of the VM wer recorded using Tensiomyography (TMG) before and after CWI, HWI or passive resting and up to one-hour post-application. The main outcomes obtained were muscle displacement and velocity of deformation according to limb size (Dmr and Vdr). Our results showed a significant effect of time (F(3.9,405) =32.439; p <0.001; η2p =0.29) and the interaction between time and temperature (F(7.9,405) =5.814; p <0.001; η2p=0.13) on Dmr but no for temperature alone (F(2,81) =2.013; p =0.14; η2p=0.04) while for Vdr, both time (F(5.2,486) =23.068; p <0.001 η2p = 0.22) and temperature (F(2,81) =4.219; p = 0.018; η2p= 0.09) as well as the interaction (F(10.4,486) =7.784; p <0.001; η2p =0.16) were found significant. Compared to CWI, HWI increased Dmr post-application and Vdr both post-application as well as 15 and 45ʹ thereafter. These findings suggest that applying HWI could be a valid alternative to CWI to promote muscle recovery. [ABSTRACT FROM AUTHOR]