Search results for "isometric"
showing 10 items of 535 documents
Cardiopulmonary loading in motocross riding
2007
The present study was designed to examine physiological responses during motocross riding. Nine Finnish A-level motocross riders performed a 15-min ride at a motocross track and a test of maximal oxygen uptake (VO2max) in the laboratory. Cardiopulmonary strain was measured continuously during the ride as well as in the VO2max test. During the ride, mean VO2 was 32 ml x kg(-1) x min(-1) (s = 4), which was 71% (s = 12) of maximum, while ventilation (V(E)) was 73% (s = 15) of its maximum. The relative VO2 and V(E) values during the riding correlated with successful riding performance (r = 0.80, P < 0.01 and r = 0.79, P < 0.01, respectively). Mean heart rate was maintained at 95% (s = 7) of its…
Effect of electrical stimulation training on the contractile characteristics of the triceps surae muscle.
1993
This study aimed to assess the effects of training using electrical stimulation (ES) on the contractile characteristics of the triceps surae muscle. A selection of 12 subjects was divided into two groups (6 control, 6 experimental). The ES sessions were carried out using a stimulator. Flexible elastomer electrodes were used. The current used discharged pulses lasting 200 microseconds at 70 Hz. Contraction time was 5 s and rest time 15 s. The session lasted 10 min for each muscle. Training sessions were three times a week for 4 weeks. Biomechanical tests were performed using an isokinetic ergometer. Subjects performed plantar flexions of the ankle over a concentric range of movement at diffe…
Effect of Isometric Upper-Extremity Exercises on the Activation of Core Stabilizing Muscles
2007
Abstract Tarnanen SP, Ylinen JJ, Siekkinen KM, Malkia EA, Kautiainen HJ, Hakkinen AH. Effect of isometric upper-extremity exercises on the activation of core stabilizing muscles. Objective To evaluate whether isometric exercises for the upper extremities could sufficiently activate core stabilizing muscles to increase muscle strength. Design Cross-sectional study. Setting Department of physical medicine and rehabilitation at a Finnish hospital. Participants Healthy adult women (N=20). Interventions Not applicable. Main Outcome Measures Peak isometric strength of the back and abdominal muscles was measured and relative loading in 5 test exercises was evaluated by surface electromyography. Re…
Effect of Brief Daily Resistance Training on Occupational Neck/Shoulder Muscle Activity in Office Workers with Chronic Pain: Randomized Controlled Tr…
2013
Purpose. This study investigates the acute and longitudinal effects of resistance training on occupational muscle activity in office workers with chronic pain.Methods. 30 female office workers with chronic neck and shoulder pain participated for 10 weeks in high-intensity elastic resistance training for 2 minutes per day (n=15) or in control receiving weekly email-based information on general health (n=15). Electromyography (EMG) from the splenius and upper trapezius was recorded during a normal workday.Results. Adherence to training and control interventions were 86% and 89%, respectively. Compared with control, training increased isometric muscle strength 6% (P<0.05) and decreased neck…
Short-term changes in the series elastic component after an acute eccentric exercise of the elbow flexors
2001
We have studied the effect of a unique eccentric exercise session on the series elastic component (SEC) properties of human elbow flexors. Ten active females performed five sets of ten maximal eccentric contractions on an isokinetic ergometer. Maximal isometric (MVC) torque, and the corresponding myoelectrical activity (RMS) of the biceps brachii and the triceps brachii muscles were recorded before, immediately after, 48 h after, and 1 week after the exercise session. SEC compliance was also measured, using the in situ quick-release technique. Maximal eccentric torque declined significantly among the five sets of the exercise session (P < 0.01). The exercise session induced a significant de…
Neuromuscular adaptations and serum hormones in women during short-term intensive strength training
1992
The effects were investigated in ten women of intensive heavy resistance strength training lasting for 3 weeks on electromyographic (EMG) activity, muscle cross-sectional area (CSA) and voluntary force production characteristics of leg extensor muscles. Blood samples for the determinations of serum hormones were taken from five of the subjects. Significant increases occurred in the higher force portions of the isometric force-time curve with an increase of 9.7 (SD 8.4)% (P less than 0.01) in maximal peak force. An increase of 15.8 (SD 20.9)% (P less than 0.05) took place also in the maximal neural activation (integrated EMG) of the trained muscles, while an enlargement of 4.6 (SD 7.4)% (P l…
Effects of intra-session exercise sequence during water-based concurrent training.
2013
The aim was to investigate the effects of the intra-session exercise order during water-based concurrent training on the neuromuscular adaptations in young women. 26 women (25.1±2.9 years) were placed into 2 groups: resistance prior to (RA) or after (AR) aerobic training. Subjects performed resistance (sets at maximal effort) and aerobic training (exercises at heart rate corresponding to the second ventilatory threshold) twice a week over 12 weeks, performing both exercise types in the same training session. Upper (elbow flexion) and lower-body (knee extension) one-repetition maximum test (1RM) and peak torque (PT) were evaluated. The muscle thickness (MT) of upper (sum of MT of biceps brac…
Neuromuscular and hormonal responses in elite athletes to two successive strength training sessions in one day
1988
Acute neuromuscular and endocrine adaptations to weight-lifting were investigated during two successive high intensity training sessions in the same day. Both the morning (I) (from 9.00 to 11.00 hours) and the afternoon (II) (from 15.00 hours to 17.00 hours) training sessions resulted in decreases in maximal isometric strength (p less than 0.01 and less than 0.05), shifts (worsening) in the force-time curve in the absolute scale (p less than 0.05 and ns.) and in decreases in the maximal integrated EMG (p less than 0.01 and less than 0.05) of the selected leg extensor muscles. Increases in serum total (p less than 0.05) and free testosterone (p less than 0.01) and in cortisol (p less than 0.…
EMG, muscle fibre and force production characteristics during a 1 year training period in elite weight-lifters.
1987
The effects of a 1 year training period on 13 elite weight-lifters were investigated by periodical tests of electromyographic, muscle fibre and force production characteristics. A statistically non-significant increase of 3.5% in maximal isometric strength of the leg extensors, from 4841 +/- 1104 to 5010 +/- 1012 N, occurred over the year. Individual changes in the high force portions of the force-velocity curve correlated (p less than 0.05-0.01) with changes in weight-lifting performance. Training months 5-8 were characterized by the lowest average training intensity (77.1 +/- 2.0%), and this resulted in a significant (p less than 0.05) decrease in maximal neural activation (IEMG) of the m…
The cross-sectional area of the gluteus maximus muscle varies according to habitual exercise loading: Implications for activity-related and evolution…
2015
Greater size of the gluteus maximus muscle in humans compared to non-human primates has been considered an indication of its function in bipedal posture and gait, especially running capabilities. Our aim was to find out how the size of the gluteus maximus muscle varies according to sports while controlling for variation in muscle strength and body weight. Data on gluteus maximus muscle cross-sectional area (MCA) were acquired from magnetic resonance images of the hip region of female athletes (N=91), and physically active controls (N=20). Dynamic muscle force was measured as counter movement jump and isometric knee extension force as leg press. Five exercise loading groups were created: hig…