Search results for " exercise"
showing 10 items of 1621 documents
Anaerobic performance testing of professional soccer players 1995-2010
2013
Purpose:To compare sprint and countermovement-jump (CMJ) performance among competitive soccer players as a function of performance level, field position, and age. In addition, the authors wanted to quantify the evolution of these physical characteristics among professional players over a 15-y period.Methods:939 athletes (22.1 ± 4.3 y), including national-team players, tested 40-m sprint with electronic timing and CMJ on a force platform at the Norwegian Olympic Training Center between 1995 and 2010.Results:National-team and 1st-division players were faster (P < .05) than 2nd-division (1.0–1.4%), 3rd- to 5th-division (3.0–3.8%), junior national-team (1.7–2.2%), and junior players (2.8–3.7…
Differential contributions of ankle plantarflexors during submaximal isometric muscle action: A PET and EMG study
2014
Abstract The objective of this study was to investigate the relative contributions of superficial and deep ankle plantarflexors during repetitive submaximal isometric contractions using surface electromyography (SEMG) and positron emission tomography (PET). Myoelectric signals were obtained from twelve healthy volunteers (27.3±4.2yrs). A tracer ([ 18 F]-FDG) was injected during the exercise and PET scanning was done immediately afterwards. The examined muscles included soleus (Sol), medial gastrocnemius (MG), lateral gastrocnemius (LG), and flexor hallucis longus (FHL). It was found that isometric maximal voluntary contraction (MVC) force, muscle glucose uptake (GU) rate, and SEMG of variou…
SYMPATHETIC NERVOUS SYSTEM AND BLOOD-PRESSURE CONTROL IN ESSENTIAL HYPERTENSION
1978
Abstract In normotensive subjects an inverse correlation was observed between an index of sympathetic nervous activity (the plasma-noradrenaline concentration during physical exercise) and reactivity to exogenous noradrenaline. This relationship was invariably disturbed in age-matched patients with essential hypertension. Multiple-regression analysis revealed a highly significant correlation between the combination of both factors and the height of mean arterial blood-pressure ( r =0·91). The findings suggest that sympathetic nervous activity and pressor response to noradrenaline together form an important determinant of the arterial blood-pressure level. An inverse relationship could be de…
Diet high in protein-rich foods with structured sport activity may be useless to lose fat mass and maintain fat-free mass
2020
Background The aim of this study was to demonstrate that a normal protein diet along with minimal sports activity can be enough to lose fat mass and maintain muscle mass. Methods All participants were prescribed a hypocaloric nutritionally balanced Mediterranean-style diet tailored to the individual for 8 weeks. Body composition and energy expenditure were measured. Sedentary patients (G1) were only recommended to perform minimal aerobic training, while sport subjects (G2) were prescribed structured physical activity and higher calorie and protein contents in the diet. Results There were no significant differences between the two groups for any of the measured parameters. Conclusions The mo…
Pain Neurophysiology Education and Therapeutic Exercise for Patients With Chronic Low Back Pain: A Single-Blind Randomized Controlled Trial.
2018
Abstract: Objective To assess the effect of a pain neurophysiology education (PNE) program plus therapeutic exercise (TE) for patients with chronic low back pain (CLBP). Design Single-blind randomized controlled trial. Setting Private clinic and university. Participants Patients with CLBP for ≥6 months (N=56). Interventions Participants were randomized to receive either a TE program consisting of motor control, stretching, and aerobic exercises (n=28) or the same TE program in addition to a PNE program (n=28), conducted in two 30- to 50-minute sessions in groups of 4 to 6 participants. Main Outcomes Measures The primary outcome was pain intensity rated on the numerical pain rating scale whi…
Numerical relations and skill level constrain co-adaptive behaviors of agents in sports teams.
2014
Similar to other complex systems in nature (e.g., a hunting pack, flocks of birds), sports teams have been modeled as social neurobiological systems in which interpersonal coordination tendencies of agents underpin team swarming behaviors. Swarming is seen as the result of agent co-adaptation to ecological constraints of performance environments by collectively perceiving specific possibilities for action (affordances for self and shared affordances). A major principle of invasion team sports assumed to promote effective performance is to outnumber the opposition (creation of numerical overloads) during different performance phases (attack and defense) in spatial regions adjacent to the bal…
Determinants of leisure-time physical activity and future intention to practice in Spanish college students
2009
Few studies analyze determinants and patterns of physical activity among college students, so it has not been possible to carry out effective interventions to promote this practice. The aim of this study was to analyze the associations between some personal, social, and environmental determinants, practice of physical activity and future intention to practice in a sample of 639 university students (321 men and 318 women), mean age 21.43 years (+/- 2.78). Physical fitness self-perception, physical activity history, and coach's support to practice physical activity have a direct effect on the practice of physical activity and an indirect effect on future intention to practice, both in men and…
Behavior of fascicles and the myotendinous junction of human medial gastrocnemius following eccentric strength training
2009
This study is the first in which measurements of thickness, fascicle angle and length, and tendon elongation were combined to examine the impact of eccentric strength training on both muscle architecture and tendinous structures. Eighteen healthy male subjects were divided into an eccentric strength training group (n = 10) and a control group (n = 8). The training program consisted of 18 sessions of eccentric exercises over a 7-week period. All subjects were tested at baseline and after the last training session. Using ultrasound imaging, the fascicle angle and length and thickness of the medial gastrocnemius (MG) were analyzed at rest (i.e., theta(p), Fl(p), and t(p), respectively), at 50%…
Physical activity in adulthood: genes and mortality.
2015
AbstractObservational studies report a strong inverse relationship between leisure-time physical activity and all-cause mortality. Despite suggestive evidence from population-based associations, scientists have not been able to show a beneficial effect of physical activity on the risk of death in controlled intervention studies among individuals who have been healthy at baseline. On the other hand, high cardiorespiratory fitness is known to be a strong predictor of reduced mortality, even more robust than physical activity level itself. Here, in both animals and/or human twins, we show that the same genetic factors influence physical activity levels, cardiorespiratory fitness and risk of de…
The benefits of sustained leisure-time physical activity on job strain
2010
Background The long-term effects of leisure-time physical activity (LTPA) on job strain have not been assessed in a large prospective population-based cohort study. Aims To examine the relationship between the LTPA and the prevalence of job strain. Methods The participants were 861 full-time employees (406 men and 455 women), aged 24―39 years in 2001, from the ongoing Cardiovascular Risk in Young Finns Study. LTPA was assessed using a self-report questionnaire in 1992 and in 2001. The participants were grouped into four categories according to tertiles of LTPA index at two time points: persistently active, increasingly active, decreasingly active and persistently inactive. Job strain was me…