Search results for "MUSCLE POWER"
showing 10 items of 23 documents
Effects of short inter-repetition rest periods on power output losses during the half squat exercise
2016
BACKGROUND: Cluster training is being increasingly used to develop muscular power. OBJECTIVE: To determine the effects of short inter-repetition rest (IRR) periods on the capacity to maintain maximal levels of power output. METHODS:In afirst session, 16 active-duty soldiers performed a progressive loading test toestablish the load linked tomaximal power (optimal load, OL), and the half squat 1-repetition maximum. In Session 2, six individual sets of repetitions performed to failure (or a maximum of 20 repetitions) were conducted using the loads OL, low (LL, 15% below OL), and high (HL, 15% above OL) as quickly as possible. For each load, participants performed one set without rest between r…
Effects of heavy barbell hip thrust vs back squat on subsequent sprint performance in rugby players
2020
The objective of this research was to compare the effect of Post-Activation Performance Enhancement (PAPE) exerted on the back squat (BS) versus the barbell hip thrust (HT) on the sprint performance (5- and 10-m). 17 male amateur rugby players participated in the study (age 22.14 ± 2.52 years; body mass 81.06 ± 9.6 kg; height 1.78 ± 0.05 m). All participants performed a dynamic maximum strength test (3RM) in BS and HT at maximum speed. Two randomized sessions were performed inducing PAPE using BS or HT trough three series with three repetitions at 85% 1RM eight minutes before the sprint tests. An ANOVA of repeated measurement, found no differences in the time for 5-m (F = 0.398, P = 0.537, …
Postmenopausal hormone replacement therapy modifies skeletal muscle composition and function: a study with monozygotic twin pairs
2009
We investigated whether long-term hormone replacement therapy (HRT) is associated with mobility and lower limb muscle performance and composition in postmenopausal women. Fifteen 54- to 62-yr-old monozygotic female twin pairs discordant for HRT were recruited from the Finnish Twin Cohort. Habitual (HWS) and maximal (MWS) walking speeds over 10 m, thigh muscle composition, lower body muscle power assessed as vertical jumping height, and maximal isometric hand grip and knee extension strengths were measured. Intrapair differences (IPD%) with 95% confidence intervals (CI) were calculated. The mean duration of HRT use was 6.9 ± 4.1 yr. MWS was on average 7% (0.9 to 13.1%, P = 0.019) and muscle…
Effects of strength training on muscle power and serum hormones in middle-aged and older men.
2001
Effects of 16-wk strength training on maximal strength and power performance of the arm and leg muscles and serum concentrations [testosterone (T), free testosterone (FT), and cortisol] were examined in 11 middle-aged (M46; 46 ± 2 yr) and 11 older men (M64; 64 ± 2 yr). During the 16-wk training, the relative increases in maximal strength and muscle power output of the arm and leg muscles were significant in both groups ( P < 0.05–0.001), with no significant differences between the two groups. The absolute increases were higher ( P < 0.01–0.05) in M46 than in M64 mainly during the last 8 wk of training. No significant changes were observed for serum T and FT concentrations. Analysis o…
Associations between muscle strength, spirometric pulmonary function and mobility in healthy older adults
2014
Background: Pathological obstruction in lungs leads to severe decreases in muscle strength and mobility in patients suffering from chronic obstructive pulmonary disease. The purpose of this study was to investigate the interdependency between muscle strength, spirometric pulmonary functions and mobility outcomes in healthy older men and women, where skeletal muscle and pulmonary function decline without interference of overt disease. Methods: 135 69 to 81‐yr‐old participants were recruited into the cross‐sectional study, which was performed as a part of European study MyoAge. Full, partial and no mediation models were constructed to assess the interdependency between muscle strength (handgr…
Effects of soluble milk protein or casein supplementation on muscle fatigue following resistance training program: a randomized, double-blind, and pl…
2014
International audience; Background: The effects of protein supplementation on muscle thickness, strength and fatigue seem largely dependent on its composition. The current study compared the effects of soluble milk protein, micellar casein, and a placebo on strength and fatigue during and after a resistance training program. Methods: Sixty-eight physically active men participated in this randomized controlled trial and underwent 10 weeks of lower-body resistance training. Participants were randomly assigned to the Placebo (PLA), Soluble Milk Protein (SMP, with fast digestion rate) or Micellar Casein (MC, with slow digestion rate) group. During the 10-week training period, participants were …
Methods and Strategies for Reconditioning Motor Output and Postural Balance in Frail Older Subjects Prone to Falls
2021
In frail older subjects, the motor output of the antigravity muscles is fundamental in resisting falls. These muscles undergo accelerated involutions when they are inactive and the risk of falling increases during leisure and domestic physical activity. In order to reduce their risk of falling, frail older subjects limit their physical activities/exercises. The problem is that the less they exercise, the less they are able to exercise and the greater the risk in exercising. Hence, a vicious circle sets up and the antigravity muscles inevitably continue to deteriorate. This vicious circle must be broken by starting a reconditioning program based on developing the strength of antigravity musc…
Leg extension power asymmetry and mobility limitation in healthy older women
2005
Objective To investigate the association of asymmetry in leg extension power (LEP) with walking and standing balance. Design Cross-sectional analysis. Setting Research laboratory. Participants Healthy female twins (N=419), ages 63 to 75 years. Interventions Not applicable. Main Outcome Measures The LEP difference between the stronger and the weaker leg, measured with the Nottingham power rig, was calculated. Ten-meter maximal walking velocity was assessed in a laboratory corridor on a wide (170cm) and narrow (35cm) track, and the ability to maintain tandem stance for 20 seconds was recorded. Results The mean LEP difference ± standard deviation between the legs was 15%±9% (P<.001). Those wit…
Constant Power Model in Arm Rotation—A New Approach to Hill’s Equation
2014
The purpose of this study was to further develop the constant power model of a previous study and to provide the final solution of Hill’s force-velocity equation. Forearm and whole arm rotations of three different subjects were performed downwards (elbow and shoulder extension) and upwards (elbow and shoulder flexion) with maximum velocity. These arm rotations were recorded with a special camera system and the theoretically derived model of constant maximum power was fitted to the experimentally measured data. The moment of inertia of the arm sectors was calculated using immersion technique for determining accurate values of friction coefficients of elbow and whole arm rotations. The experi…
Modeling the force – velocity relationship in arm movement
2012
Modeling the force-velocity dependence of a muscle-tendon unit has been one of the most interesting objectives in the field of muscle mechanics. The so-called Hill’s equation [1,2] is widely used to describe the force-velocity relationship of muscle fibers. Hill’s equation was based on the laboratory measurements of muscle fibers and its application to the practical measurements in muscle mechanics has been problematic. Therefore, the purpose of this study was to develop a new explicit calculation method to determine the force-velocity relationship, and test its function in experimental measurements. The model was based on the motion analysis of arm movements. Experiments on forearm rotatio…