Search results for "Exercise physiology"
showing 10 items of 185 documents
Results of an Observational Cohort Study of Hyperuricemia as a Predictor of Poor Physical Performance in the Elderly
2017
Objective: Hyperuricemia is frequent in older people and associated with several medical conditions. The relationship between hyperuricemia and physical performance is limited. We aimed to investigate the association between hyperuricemia and physical performance over a 4.4-year followup in the elderly. Methods: A total of 1,904 community-dwelling older participants were followed for a mean of 4.4 years. Hyperuricemia at baseline was defined using serum uric acid concentrations ≥6 and ≥7 mg/dl for women and men, respectively. Objective physical performance tests measured included the Short Physical Performance Battery (SPPB), 4-meter gait speed, chair-stands time, leg extension and flexion,…
Biomechanical Comparison Between Sprint Start, Sled Pulling, and Selected Squat-Type Exercises
2013
The purpose of this study was to compare kinetics, kinematics, and muscle activity among sprint start, sled pulling, and selected squat-type exercises (countermovement jumps [CMJs] and 1/2-squats with various loads) and also to examine how these exercises correlate with the performance time of the block start (10 m). Nine male athletes (4 sprinters, 3 decathlonists, 1 long jumper, and 1 triple jumper: age = 24.9 ± 3.9 years; 100-m record = 11.35 ± 0.29 seconds; track and field training years = 11.8 ± 3.1 years) volunteered as subjects. The comparisons were made with regard to the block phase (the phase of force production toward starting blocks) of the block start. In nearly all exercises, …
Wrist-worn accelerometers in assessment of energy expenditure during intensive training
2012
We assessed the ability of the Polar activity recorder (AR) to measure energy expenditure (EE) during military training. Twenty-four voluntary male conscripts participated in the study and wore an AR on the non-dominant wrist 24 h a day for 7 d. The AR analyzed and stored the frequency of hand movements (f_hand) into memory at 1 min intervals. The relationship between f_hand and EE was studied over a 7 d period of military training using the doubly labeled water (DLW) technique. In addition, the relationship between f_hand and EE was analyzed during walking and running on a treadmill with an indirect calorimeter (IC), and f_hand was measured during a supervised 45 min field march test where…
Can exercise-induced muscle damage be related to changes in skin temperature?
2018
Measurement of skin temperature using infrared thermography has become popular in sports, and has been proposed as an indicator of exercise-induced muscle damage after exercise. However, the relationship between skin temperature and exercise-induced muscle damage is still unclear. Here we set out to investigate the relationship between skin temperature and exercise-induced muscle damage.Twenty untrained participants completed a protocol of exercise for calf muscles. Before and after exercise blood samples were collected to determine creatine kinase and acetylcholinesterase activity. Thermal images were recorded from the exercised muscles to determine skin temperature. Delayed onset muscle s…
Control of glycolysis in vertebrate skeletal muscle during exercise
1996
The gastrocnemius muscle of the frog (Rana temporaria) has a high capacity for anaerobic glycolysis from glycogen. Glycolytic metabolites and effectors of phosphofructokinase, particularly the hexose bisphosphates, were followed in muscle during exercise (swimming between 5 s and 5 min), recovery (rest for up to 2 h after 5 min of swimming), and repeated exercise (swimming for up to 60 s after 2 h of recovery). Glycogen phosphorylase and phosphofructokinase were swiftly activated with exercise. The hexose bisphosphates followed markedly different time courses. Fructose 1,6-bisphosphate was transiently increased in both exercise and repeated exercise. This appears to be an effect rather tha…
Effects of combined strength and sprint training on regulation of muscle contraction at the whole-muscle and single-fibre levels in elite master spri…
2008
The aims of this study were to investigate the mechanisms underlying (1) the ageing-related motor handicap at the whole muscle, cellular, contractile protein and myonuclear levels; and (2) ageing-related differences in muscle adaptability.In vivo muscles function was studied in the knee extensors. Decreases were observed in isokinetic and isometric torque outputs in old age in the sedentary men and women and elite master sprinters. A 20-week long specific sprint and resistance training successfully improved the maximal isometric force and rate of force development in a subgroup of master sprinters.In vitro measurements were performed in muscle biopsies from the vastus lateralis muscle. Immu…
Impact of ''off-label'' use of ivabradine on exercise capacity, gas exchange, functional class, quality of life, and neurohormonal modulation in pati…
2010
Background: Epidemiologic studies indicate that elevated heart rate (HR) is an independent risk factor for mortality and morbidity in patients (pts) with chronic heart failure (CHF). Clinical trials with b-blockers suggest that HR reduction is an important mechanism of their benefit in pts with stable CHF. Pharmacologic inhibition of the If current now provides the opportunity of pure HR reduction. The purpose of this study was to evaluate the impact of ‘‘Off-Label’’ use of ivabradine on exercise capacity, gas exchange, functional class, quality of life, and neurohormonal modulation in pts with ischemic CHF. Methods: Between January 2008 and June 2008, a graded maximal exercise test with re…
Acute hormonal and neuromuscular responses and recovery to forced vs maximum repetitions multiple resistance exercises.
2003
Acute hormonal and neuromuscular responses and recovery three days after the exercises were examined during the maximum repetitions (MR) and forced repetitions (FR) resistance exercise protocols in 16 male athletes. MR included 4 sets of leg presses, 2 sets of squats and 2 sets of knee extensions (with 12 RM) with a 2-min recovery between the sets and 4 min between the exercises. In FR the initial load was chosen to be higher than in MR so that the subject could not lift 12 repetitions per set by himself. After each set to failure the subject was assisted to perform the remaining repetitions to complete the 12 repetitions per set. Thus the exercise intensity was greater in FR than in MR. Bo…
Fuel selection during short-term submaximal treadmill exercise in the cold is not affected by pre-exercise low-intensity shivering.
2014
Exercise and shivering rely on different metabolic pathways and consequently, fuel selection. The present study examined the effects of a pre-exercise low-intensity shivering protocol on fuel selection during submaximal exercise in a cold environment. Nine male subjects exercised 4 times for 60 min at 50% (LOW) or 70% (MOD) of their peak oxygen consumption on a motorized treadmill in a climatic chamber set at 0 °C with (SHIV) and without (CON) a pre-exercise cooling protocol, inducing low-intensity shivering. Thermal, cardiorespiratory and metabolic responses were measured every 15 min whereas blood samples were collected every 30 min to assess serum nonesterified fatty acids (NEFA), glyce…
Metabolic and anti-inflammatory effects of a home-based programme of aerobic physical exercise
2013
Summary Aims Regular exercise demonstrated the ability to provide enormous benefits to many diseases, atherosclerotic-based, degenerative and neoplastic, but also to grant anti-inflammatory actions, assessed by various authors in different populations. Despite of these clear benefits, many patients are unable to attain long-term results through chronic physical activity for different causes. On this basis, the aim of our study was to assess the metabolic and anti-inflammatory effects of a home-based programme of fast walking in patients affected by metabolic syndrome (MS). Materials and methods We enrolled 176 subjects with MS as stated by ATP III criteria. Patients were invited to walk for…