Search results for "Energy Metabolism"
showing 10 items of 331 documents
Postprandial thermogenesis and alimentary sensory stimulation in human subjects
1999
OBJECTIVE: To study the role of alimentary sensory stimulation on the thermic effect of food. SUBJECTS: Nine male healthy volunteers (age: 20-34y, body mass index (BMI): 17.4-25.3 kg/m 2 ). DESIGN AND MEASUREMENTS: Four experimental situations were investigated on different days. Subjects: 1) ate a four course meal containing 2582kJ (meal), 2) saw, smelt and tasted the same courses (alimentary sensory stimulation), 3) saw, smelt and tasted non-alimentary substances (non-alimentary sensory stimulation), 4) received directly into the stomach the previous meal (tube feeding). Energy expenditure (EE) was measured over a 20 min rest period, then for 110 min. RESULTS: The changes over midday rest…
Mechanical step variability during treadmill running.
1995
The present study was designed to study intra-individual step variability measured both on vertical displacement of the body (delta Z) and on step time (delta t) parameters by means of a kinematic arm and during treadmill running. A group of 17 subjects ran successively at 60%, 80%, 100% and 140% of their maximal aerobic velocity (Vamax). The total number of steps analysed was 6116. The absolute delta Z step variability (sigma delta Z) ranged between 5 mm and 21 mm while the absolute delta t variability (sigma delta t) ranged between 6 ms and 40 ms. Step variabilities were due to step asymmetry (from 38.5% to 48.5% of the step variability) and to stride variability. For submaximal velocitie…
Differences in ground reaction forces and shock impacts between nordic walking and walking.
2014
The regular practice of Nordic walking (NW) has increased in recent years, in part thanks to the health benefits described by the scientific literature. However, there is no consensus on the effects of shock-impact absorption during its practice. Purpose: The aim of this study was to compare the levels of impact and ground reaction forces (GRF) between NW and walking (W). Method: Twenty physically active and experienced participants were assessed using a dynamometric platform and accelerometry analysis. Results: The results show statistically significantly higher levels of acceleration in the tibia (12%) and head (21%) during NW compared with W. Equally, GRF were significantly higher (27%) …
Acute neuromuscular and metabolic responses to combined strength and endurance loadings: the "order effect" in recreationally endurance trained runne…
2014
The study examined the acute neuromuscular and metabolic responses and recovery (24 and 48 h) to combined strength and endurance sessions (SEs). Recreationally endurance trained men (n = 12) and women (n = 10) performed: endurance running followed immediately by a strength loading (combined endurance and strength session (ES)) and the reverse order (SE). Maximal strength (MVC), countermovement jump height (CMJ), and creatine kinase activity were measured pre-, mid-, post-loading and at 24 and 48 h of recovery. MVC and CMJ were decreased (P0.05) at post-ES and SE sessions in men. Only MVC decreased in ES and SE women (P0.05). During recovery, no order differences in MVC were observed between…
High-Intensity Interval Resistance Training (HIRT) influences resting energy expenditure and respiratory ratio in non-dieting individuals
2012
Abstract Background The benefits of exercise are well established but one major barrier for many is time. It has been proposed that short period resistance training (RT) could play a role in weight control by increasing resting energy expenditure (REE) but the effects of different kinds of RT has not been widely reported. Methods We tested the acute effects of high-intensity interval resistance training (HIRT) vs. traditional resistance training (TT) on REE and respiratory ratio (RR) at 22 hours post-exercise. In two separate sessions, seventeen trained males carried out HIRT and TT protocols. The HIRT technique consists of: 6 repetitions, 20 seconds rest, 2/3 repetitions, 20 secs rest, 2/3…
Tourniquet-induced changes of energy metabolism in human skeletal muscle monitored by microdialysis.
2001
Background Tourniquets are often used as part of orthopedic surgery but may cause local and remote organ injury. The authors hypothesized that the procedures used to induce ischemia (circulatory occlusion or exsanguination) may have differential effects on the metabolic state of the muscle that should be reflected in the interstitial levels of metabolites. Methods Microdialysis probes were implanted in both quadriceps femoris muscles of 18 patients. Interstitial fluid was obtained during tourniquet-induced ischemia and reperfusion and was analyzed for glucose, lactate, choline, and purines by high-performance liquid chromatography. Results At a flow rate of 2 microl/min, the average baseli…
Age and sex differences in blood lactate response to sprint running in elite master athletes.
2005
The effect of age and sex on anaerobic glycolytic capacity in master athletes is currently unclear. To study this issue, we determined blood lactate concentrations after competitive sprint running in male and female master athletes of different age. Eighty-one men (40-88 yrs) and 75 women (35-87 yrs) participating in the sprint events (100-m, 200-m, 400-m) in the European Veterans Athletics Championships were studied. Blood samples were taken from the fingertip and analysed for peak lactate concentration ([La]bpeak). The [La]bpeak following 100-m to 400-m races showed a curvilinear decline (p < 0.001-0.05) with age in both men and women. However, the age related differences in the [La]b…
Enzyme activities in muscle and connective tissue of M. vastus lateralis in habitually training and sedentary 33 to 70-year-old men
1975
A cross-sectional study was carried out to examine the activities of certain enzymes representing aerobic and anaerobic energy metabolism as well as the biosynthesis of collagen of M. vastus lateralis in 23 male endurance athletes in habitual training, aged 33 to 70 years. 23 sedentary healthy men of corresponding ages were selected for the control group. The mean maximal oxygen uptake of the trained subjects was 53.6 ml · kg−1 · min−1 and that of the control subjects 36.3 ml · kg−1 · min−1. As compared to the control group the trained subjects had significantly higher values in the muscle malate dehydrogenase, succinate dehydrogenase and prolyl hydroxylase activities, whereas the opposite …
Effects of marathon running on running economy and kinematics.
2000
The present study was designed to investigate interactions between running economy and mechanics before, during, and after an individually run marathon. Seven experienced triathletes performed a 5-min submaximal running test on a treadmill at an individual constant marathon speed. Heart rate was monitored and the expired respiratory gas was analyzed. Blood samples were drawn to analyze serum creatine kinase activity (S-CK), skeletal troponin I (sTnI), and blood lactate (B-La). A video analysis was performed (200 frames · s−1) to investigate running mechanics. A kinematic arm was used to determine the external work of each subject. The results of the present study demonstrate that after the …
Neuromuscular, anaerobic, and aerobic performance characteristics of elite power athletes.
1984
Various aspects of neuromuscular, anaerobic, and aerobic performance capacity were investigated in four powerlifters, seven bodybuilders, and three wrestlers with a history of specific training for several years. The data (means +/- SD) showed that the three subject groups possessed similar values for maximal isometric force per unit bodyweight (50.7 +/- 9.6, 49.3 +/- 4.1, and 49.3 +/- 10.9 N/kg, respectively). However, significant (P less than 0.05) differences were observed in the times for isometric force production, so that e.g., times to produce a 30% force level were shorter for the wrestlers and bodybuilders (28.3 +/- 3.1 and 26.4 +/- 6.6 ms) than that (53.3 +/- 23.7 ms) for the powe…