In general, cardiac regulation is dominated by the sympathetic and parasympathetic nervous systems in men and women, respectively. Our recent study had revealed sex differences in the forebrain network associated with sympathoexcitatory response to baroreceptor unloading. The present study further examined the sex differences in forebrain modulation of cardiovagal response at the onset of isome...

We examined the effect of low-load, elastic band resistance training with blood flow restriction (BFR) on muscle size and arterial stiffness in older adults. Healthy older adults (aged 61-85 years) were divided into BFR training (BFR-T, n = 9) or non-BFR training (CON-T, n = 8) groups. Both groups performed low-load arm curl and triceps down exercises (four sets, total 75 repetitions for each) ...

The objective of this study was to establish the effect of moderate intensity endurance training on muscle strength in relation to hormonal changes in the body. Fifteen young, healthy men took part in 5 week endurance training performed on a cycloergometer. Before and after training program, exercise testing sessions were performed involving all participants. Training program significantly incr...

To understand the role of muscle perfusion in the sex differences of muscle fatigue, we compared the time to task failure, postcontraction (active) hyperemia, and vascular conductance for an isometric fatiguing contraction performed by young men and women with the handgrip muscles at 20% of maximal voluntary contraction (MVC) force. In study 1, the men (n = 16) were stronger than the women (n =...

The effect of isometric skeletal muscle contraction on the performance of the normal left ventricle was studied noninvasively in 20 subjects. Studies were conducted at rest and at 3 minutes of isometric hanedrip exercise at 50 per cent of maximum voluntary contraction, and consisted of simultaneous recording of left ventricular echocardiogram, external carotid pulse, phonocardiogram, and electr...

OBJECTIVES Muscle stiffness increases during muscle contraction. The purpose of this study was to determine the strength of the correlation between myotonometric measurements of muscle stiffness and surface electromyography (sEMG) measurements during various levels of voluntary isometric contractions of the biceps brachii muscle. SUBJECTS Eight subjects (four female; four male), with mean age...

BACKGROUND It is unclear whether mental simulation without actual muscle contraction associated with actual motion can increase the excitability of the spinal neural function. OBJECTIVE To determine the best method for mental simulation without actual muscle contraction, we analyzed the F-wave of thenar muscles after stimulating the median nerve by motor imagery whilst holding the sensor of a...

Lower limb actions such as jumping, standing and squatting all require both legs to act equally to provide the most efficient movement, and limit the development of bilateral asymmetries which may lead to unilateral trauma and reduced performance. In this study ten male volleyball players with age ranged from eighteen to twenty four years of Lakshmibai National Institute of Physical Education, ...

The in vivo strain properties of human skeletal muscle-tendon complexes are poorly understood, particularly following chronic periods of reduced load bearing. We studied eight healthy volunteers who underwent 4 wk of unilateral lower limb suspension (ULLS) to induce chronic unloading. Before and after the ULLS, maximum isometric ankle plantar flexion torque was determined by using a magnetic re...

The purpose of this study was to develop a statistical model to describe the electromyography (EMG) signal frequency changes during a submaximal isometric contraction. Thirty subjects performed a 30-second isometric contraction of the biceps brachii muscle at 80% of the maximal voluntary isometric force. Surface EMG electrodes recorded electrical activity of the biceps brachii. Zero-Crossing-Ra...