Search results for "Energy Metabolism"
showing 10 items of 331 documents
Influence of lactate accumulation of EMG frequency spectrum during repeated concentric contractions
1983
One hundred and twenty consecutive maximal leg extensions at a constant angular velocity of 1.5 radians . s-1 were performed by nine physical education students. Integrated electromyographic (IEMG) activity and power spectrum density function (PSDF) of the EMG were recorded from m. vastus lateralis, vastus medialis and m. rectus femoris using bipolar surface electrodes. Muscle biopsies were obtained from m. vastus lateralis before and after exercise. Tissue samples were analyzed for muscle fiber type distribution and lactate and glycogen concentration. Muscle force and IEMG decreased in parallel over the exercise period. Thus, the IEMG/force ratio was unchanged. Mean power frequency (MPF) o…
Electromyographic activity related to aerobic and anaerobic threshold in ergometer bicycling
1985
Electromyographic activity (EMG) of the knee extensor musculature (m. vastus lateralis, m. vastus medialis, m. rectus femoris), triceps surae (m. gastrocnemius, m. soleus) and m. tibialis anterior was studied in ergometer bicycling at five different power outputs around aerobic (AerT) and anaerobic (AnT) thresholds. EMGs were sampled with surface electrodes for ten revolutions at the beginning, in the middle and at the end of each work load and integrated (IEMG) separately for each of the muscles and for the descending (work) and ascending (rest) phase of the revolution. The mean power frequency (MPF) of the power spectral density function for the descending periods was also calculated. The…
Basal metabolic rate in narcoleptic patients.
2009
PATIENTS SUFFERING FROM NARCOLEPSY TEND TO BE OBESE.1,2 AMONG OTHER HYPOTHESES LOWER RESTING ENERGY EXPENDITURE HAS BEEN SUSPECTED to be the cause of the narcolepsy-associated obesity.3,4 The use of indirect calorimetry is a well-established noninvasive method to measure the energy expenditure (EE) and the resting (basal) metabolic rate (BMR). Chabas et al. recently published an evaluation of eating behavior and energy balance of 7 typical and 6 atypical narcoleptic patients and 9 controls using indirect calorimetry. Narcoleptic patients were found to have a lower energy expenditure (EE) than controls (n = 13, P = 0.07). Thus, it was concluded that narcolepsy associated obesity could be the…
Does anaerobic threshold correlate with maximal lactate steady-state?
1992
The aim of this study was to compare the 'anaerobic threshold' (AnT) of subjects determined during a continuous 2-min incremental exercise test until exhaustion and the 'maximal lactate steady-state' (BLaSsmax) determined during prolonged exercise at constant loads corresponding to the subjects' AnT and/or 5-25% above and below it. Seventeen subjects performed an incremental exercise test and 1-5 prolonged exercise tests on a cycle ergometer until exhaustion at intervals of 1 week, and work rates, oxygen uptake (VO2) values and brachial venous blood lactate (BLa) levels were measured. It was proposed that when exercising at a constant workload below AnT, BLa would fall after having reached …
Effects of strength and endurance training on metabolic risk factors in healthy 40â65-year-old men
2009
This study compared 21 weeks of combined high-intensity strength and endurance training with endurance or strength training only on metabolic risk factors in 40-65-year-old men. The healthy men (n=63) were randomized into endurance (E), strength (S), combined strength and endurance training (SE) and control (C) groups. S and E trained two times a week and SE 2+2 times a week. Systolic (SBP) and diastolic blood pressure decreased significantly both in E (-6+/-8 and -4+/-6 mmHg) and in S (-9+/-8 and -5+/-7 mmHg), but not in SE or C (P=0.003 for the difference in the changes of SBP between the groups). The changes in serum glucose and insulin during an oral glucose tolerance test did not diffe…
Enzyme activities and glycogen concentration in skeletal muscle in alcoholism. The effect of abstinence and physical conditioning.
1974
. Muscle metabolism of chronic alcoholics has been studied using a muscle biopsy technique immediately after a drinking period, after 6–7 days' abstinence and after one month's physical conditioning. The activities of CPK, HK, LDH, MDH and SDH were significantly decreased in musculus vastus lateralis for 1–2 days after an alcoholic debauch. The enzyme activities of the alcoholics, who either had been abstinent for 6–7 days or in addition conditioned for one month, did not differ from those of the controls. The concentration of muscle glycogen was at the same level in both groups, but in bicycle ergometer work of an equal relative intensity the alcoholics used more glycogen than the control …
A low resting metabolic rate is associated with metabolic syndrome
2007
Background & aims: The metabolic syndrome is associated with central accumulation of fat. Previous studies showed that some obese subjects are characterized by a sparing energy metabolism. The aim of this study was to investigate whether obese subjects with metabolic syndrome have a lower resting metabolic rate than obese subjects without metabolic syndrome. Methods: Forty obese subjects were divided into three groups according to the presence of metabolic syndrome and type 2 diabetes; 15 non-obese healthy control subjects were also enrolled. Body composition (bio-impedance analysis) and resting metabolic rate (indirect calorimetry) were performed. Results: The group with metabolic syndrome…
Sports massage with ozonised oil or non-ozonised oil: Comparative effects on recovery parameters after maximal effort in cyclists
2013
Abstract OBJECTIVES: To study the effects of passive rest (PR) and sports massage with (SMOZO) and without (SM) ozonised oil on sports performance psycho-physiological indices in competitive amateur cyclists after 3 pre-fatiguing Wingate cycle and post-recovery ramp tests. DESIGN: An intra-subjects experimental design with repeated measures. SETTING: Department of Human Anatomy and Physiology, University of Padua. PARTICIPANTS: Fifteen male competitive cyclists (age: 27 ± 3.5 years, body weight: 77.6 ± 8.3 kg, height: 178 ± 7.7 cm) were studied. MAIN OUTCOME MEASURES: Subjects' power output (P), heart rate (HR), Visual Analogue Scale (VAS) score and blood lactate (BL) clearance in response …
Muscle inactivity is adversely associated with biomarkers in physically active adults.
2015
PURPOSE While the lack of muscular activity is a proposed trigger for metabolic alterations, this association has not been directly measured. We examined the associations between EMG-derived muscle inactivity and activity patterns and cardiometabolic biomarkers in healthy, physically active adults. METHODS Data for this cross-sectional study were pooled from two studies (EMG24 and InPact), resulting in a sample of 150 individuals without known chronic diseases and with high-quality EMG data (female n = 85, male n = 65, age = 38.8 ± 10.6 yr, body mass index = 23.8 ± 3.1 kg·m⁻²). EMG was measured during one to three typical weekdays using EMG shorts, measuring quadriceps and hamstring muscle …
Differences in mechanical efficiency between power- and endurance-trained athletes while jumping
1995
Mechanical efficiency (ME) of jumping exercises was compared between power-trained (n = 11) and endurance-trained athletes (n = 10) using both a biomechanical and a physiological approach. In drop jumps and in stretch-shortening cycle exercise on a special sledge (sledge jumps), the subjects performed 60 muscle actions from a dropping height of optimum minus 40 cm (O − 40), as well as from dropping heights of optimum (O) and optimum plus 40 cm (O + 40). Thus, they were tested in six different tests which lasted for a total of 3 min for each. The mean ME values in the drop jumps from the lowest dropping height upwards were as follows: 23.8 (SD 5.3)%, 35.5 (SD 10.8)% and 39.2 (SD 6.6)% for th…