Search results for " Stretching"
showing 10 items of 46 documents
Effects of Stretching on Upper-Body Muscular Performance
2008
The purpose of this investigation was to examine the influence of upper-body static stretching and dynamic stretching on upper-body muscular performance. Eleven healthy men, who were National Collegiate Athletic Association Division I track and field athletes (age, 19.6 +/- 1.7 years; body mass, 93.7 +/- 13.8 kg; height, 183.6 +/- 4.6 cm; bench press 1 repetition maximum [1RM], 106.2 +/- 23.0 kg), participated in this study. Over 4 sessions, subjects participated in 4 different stretching protocols (i.e., no stretching, static stretching, dynamic stretching, and combined static and dynamic stretching) in a balanced randomized order followed by 4 tests: 30% of 1 RM bench throw, isometric ben…
Temporal Structure of Human Gaze Dynamics Is Invariant During Free Viewing.
2015
We investigate the dynamic structure of human gaze and present an experimental study of the frequency components of the change in gaze position over time during free viewing of computer-generated fractal images. We show that changes in gaze position are scale-invariant in time with statistical properties that are characteristic of a random walk process. We quantify and track changes in the temporal structure using a well-defined scaling parameter called the Hurst exponent, H. We find H is robust regardless of the spatial complexity generated by the fractal images. In addition, we find the Hurst exponent is invariant across all participants, including those with distinct changes to higher or…
Effects of an adapted physical activity program on psychophysical health in elderly women.
2016
Giuseppe Battaglia,1,2 Marianna Bellafiore,1,2 Marianna Alesi,1,2 Antonio Paoli,3 Antonino Bianco,1,2 Antonio Palma1,2 1Department of Psychological, Pedagogical and Educational Sciences, 2Sport and Exercise Sciences Research Unit, University of Palermo, Palermo, 3Department of Biomedical Sciences, University of Padova, Padua, Italy Background: Several studies have shown the positive effects of adapted physical activity (APA) on physical and mental health (MH) during the lifetime. The aim of this study was to assess the effectiveness of a specific APA intervention program in the improvement of the health-related quality of life (QOL) and functional condition of spine in elderly women. Method…
Effects of a dynamic stretching warm-up on functional movement patterns in female hip-hop dancers
2022
Background: A large percentage of dancers suffer an injury to their musculoskeletal system at least once in their careers, as well as from pain caused by overloading or overtraining this system. A high frequency of injuries has been observed in hip-hop dancers. Before each workout, there should be a solid warm-up and stretching period. The lack of these two important elements increases the risk of injury. Aim of the study: This study aimed to examine the effects of dynamic stretching warm-ups on fundamental movement patterns in female hip-hop dancers. Material and methods: This study included 14 hip-hop female dancers, aged 15–17. Dancers participated in 6 weeks of dynamic stretching warm-u…
Acute effects of short-duration isolated static stretching or combined with dynamic exercises on strength, jump and sprint performance
2013
Summary Objective This study aimed to investigate the acute effects of a short-duration isolated static stretching or combined with dynamic plyometric exercises on the performance of some anaerobic parameters (strength, jumping and sprinting). Methods During three distinct sessions and after a standardized warm-up, 15 participants randomly performed static stretching exercises alone, static stretching combined with plyometric exercises and no stretch. Total stretch duration was 20 seconds long per muscle group (quadriceps, hamstrings and calf muscles). Tests included maximal quadriceps muscle strength, countermovement jumps and 15 m sprints. Results Whatever the condition, maximal strength …
Parallel laser micromachining based on diffractive optical elements with dispersion compensated femtosecond pulses
2013
We experimentally demonstrate multi-beam high spatial resolution laser micromachining with femtosecond pulses. The effects of chromatic aberrations as well as pulse stretching on the material processed due to diffraction were significantly mitigated by using a suited dispersion compensated module (DCM). This permits to increase the area of processing in a factor 3 in comparison with a conventional setup. Specifically, 52 blind holes have been drilled simultaneously onto a stainless steel sample with a 30 fs laser pulse in a parallel processing configuration.
Postactivation potentiation can counteract declines in force and power that occur after stretching.
2016
Stretching can decrease a muscle's maximal force, whereas short but intense muscle contractions can increase it. We hypothesized that when combined, postactivation potentiation induced by reactive jumps would counteract stretch-induced decrements in drop jump (DJ) performance. Moreover, we measured changes in muscle twitch forces and ankle joint stiffness (KAnkle ) to examine underlying mechanisms. Twenty subjects completed three DJs and 10 electrically evoked muscle twitches of the triceps surae subsequent to four different conditioning activities and control. The conditioning activities were 10 hops, 20s of static stretching of the triceps surae muscle, 20s of stretching followed by 10 ho…
Do Stretch Durations Affect Muscle Mechanical and Neurophysiological Properties?
2016
International audience; The aim of the study was to determine whether stretching durations influence acute changes of mechanical and neurophysiological properties of plantar flexor muscles. Plantar flexors of 10 active males were stretched in passive conditions on an isokinetic dynamometer. Different durations of static stretching were tested in 5 randomly ordered experimental trials (1, 2, 3, 4 and 10×30-s). Fascicle stiffness index, evoked contractile properties and spinal excitability (Hmax/Mmax) were examined before (PRE), immediately after (POST0) and 5 min after (POST5) stretching. No stretch duration effect was recorded for any variable. Moreover, whatever the stretching duration, st…
Changes of electrically elicited reflexes in hand and forearm muscles in man.
1987
Cutaneo-muscular reflexes with short and long latency excitatory phases following digital nerve stimulation were observed in the first dorsal interosseus muscle of the hand in healthy subjects. The short latency reflex was obtained also with the H-reflex method in the flexor carpi radialis muscle, stimulating the median nerve, with a mean latency (+/- SE) of 15.4 +/- 0.5 ms. The height of the subject correlated with the H-reflex latency. The amplitudes of maximal M-response and maximal H-reflex were higher in athletes than in normals. During weak voluntary contraction of the muscle studied the 50% H-reflex amplitude increased and during passive stretching of wrist flexors the resting amplit…
Changes in neural drive to calf muscles during steady submaximal contractions after repeated static stretches
2021
Key points: Repeated static-stretching interventions consistently increase the range of motion about a joint and decrease total joint stiffness, but findings on the changes in muscle and connective-tissue properties are mixed. The influence of these stretch-induced changes on muscle function at submaximal forces is unknown. To address this gap in knowledge, the changes in neural drive to the plantar flexor muscles after a static-stretch intervention were estimated. Neural drive to the plantar flexor muscles during a low-force contraction increased after repeated static stretches. These findings suggest that adjustments in motor unit activity are necessary at low forces to accommodate reduct…