Search results for " EXERCISE"
showing 10 items of 1621 documents
Effect of intramedullary gradual elongation of the shorter limb on gait patterns
2003
Background: Seven young patients were followed 52 weeks after intramedullary lengthening for limb length discrepancy (LLD). The mean LLD before surgery was 3.0 ± 1.1 cm and 1 year after surgery at the time of the nail-removal it was 0.3 ± 0.3 cm. Methods: The plantar pressures and the ground reaction forces (GRF) were recorded simultaneously with electromyographic (EMG) activities at normal and fast walking speeds. Results: Bilateral comparison indicated that the uncorrected LLD resulted in asymmetrical gait patterns. The peak pressures were higher in the lateral heel and in the medial forefoot in the longer limb as compared to the shorter limb at normal walking speed. At fast walking speed…
Exhaustive physical exercise and acid hydrolase activity in mouse skeletal muscle
1978
Adult, untrained NMRI mice were exhausted on a motor-driven treadmill by an intermittent-type running programme. Serial cryostate sections for the staining of NADH-tetrazolium reductase, beta-glucuronidase, beta-N-acetylglucosaminidase, and beta-glycerophosphatase activities and for making hematoxylin-eosin staining were cut from m. quadriceps femoris 1, 2, 3, 5, 7, and 15 days after physical exhaustion. A strong increase in the activities of beta-glucuronidase and beta-N-acetylglucosaminidase was observed 7 days after exhaustion and the activity changes, which were similar for the both glycosidases, were more prominent in the highly oxidative red compared to less oxidative white fibres. Ac…
Effect of time-of-day-specific strength training on serum hormone concentrations and isometric strength in men.
2007
A time-of-day influence on the neuromuscular response to strength training has been previously reported. However, no scientific study has examined the influence of the time of day when strength training is performed on hormonal adaptations. Therefore, the primary purpose of this study was to examine the effects of time-of-day-specific strength training on resting serum concentrations and diurnal patterns of testosterone (T) and cortisol (CORT) as well as maximum isometric strength of knee extensors. Thirty eight diurnally active healthy, previously untrained men (age 20-45 yrs) underwent a ten-week preparatory strength training period when sessions were conducted between 17:00-19:00 h. Ther…
Acute elevations in serum hormones are attenuated after chronic training with traditional isoinertial but not accentuated eccentric loads in strength…
2017
It has been proposed that the maintenance of acute hormonal responses reveal an efficacy of a training stimulus to evoke ongoing increases in strength and muscle mass. We previously observed that maximum strength continued to improve throughout a 10‐week period in an accentuated eccentric loading group (AEL) but not a traditional isoinertial loading (ISO) group. Therefore, this study investigated whether the magnitude of acute hormonal responses was greater (i.e., maintained) in AEL compared to ISO at the end of the training period. Subjects in AEL (eccentric load = concentric load + 40%) and ISO performed experimental loading tests (three sets of 10 repetitions in the leg press and knee ex…
Step vs. Two-Phase Gradual Volume Reduction Tapering Protocols in Strength Training: Effects on Neuromuscular Performance and Serum Hormone Concentra…
2020
ABSTRACT Seppanen, S and Hakkinen, K. Step vs. two-phase gradual volume reduction tapering protocols in strength training: Effects on neuromuscular performance and serum hormone concentrations. J Strength Cond Res XX(X): 000-000, 2020-This study assessed effects of 2 reduced volume tapering protocols on neuromuscular performance and serum hormone concentrations in 14 recreationally strength-trained men (21-30 years). After an 8-week strength training period subjects were divided to the step (54% volume reduction immediately) and 2-phase gradual (38% reduction for the first week and 70% for the second week) tapering groups for 2 weeks. One repetition maximum (1RM) squat, maximal isometric bi…
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,…
Seven-Weeks Gait-Retraining in Minimalist Footwear Has No Effect on Dynamic Stability Compared With Conventional Footwear.
2021
Purpose: To investigate the effects of two different running footwear conditions (transition to minimalist footwear and conventional running footwear) on dynamic postural stability before and after 7 weeks of gait retraining program, and to evaluate the effect of fatigue on dynamic stability. Method: This randomized controlled clinical trial was carried out by 42 recreational male runners, who were randomly divided into two groups; Conventional Footwear Group (CFG) (n = 22) and Minimalist Footwear Group (MFG) (n = 20). Dynamic Postural Stability Index (DPSI), in a fatigued and non-fatigued state, were assessed before and after a gait retraining program. The gait retraining program consisted…
Strength athletes are capable to produce greater muscle activation and neural fatigue during high-intensity resistance exercise than nonathletes.
2009
Acute neuromuscular responses to maximum versus forced repetition (FR) knee extension resistance exercises (4 sets of 12 repetitions [reps] with a 2-minute recovery between the sets) were examined in 4 male strength athletes (SAs) and 4 nonathletes. Maximum repetition (MR) sets were performed to voluntary exhaustion (12 repetition maximum [RM]), whereas in the FR sets, the load was greater (8RM) and the set was continued after voluntary fatigue with 4 additional assisted reps. Maximal isometric force and electromyogram (EMG) activity of the knee extensors were measured before and after the exercise, as well as 2 recovery days after the exercise. Electromyogram activity was also measured dur…
Lower-Limb Pain, Disease, and Injury Burden as Determinants of Muscle Strength Deficit After Hip Fracture
2009
Background: Hip fracture may result in an asymmetrical lower-limb strength deficit. The deficit may be related to the trauma, surgical treatment, pain, or disuse of the fractured limb. However, disease and injury burden or musculoskeletal pain in the other limb may reduce muscle strength on that side, reducing the asymmetrical deficit. The aim of our study was to explore the asymmetrical strength deficit and to determine the potential underlying factors in patients from six months to seven years after a hip fracture. Methods: The asymmetrical deficit was calculated ([fractured limb/sum of both lower limbs] x 100%) for isometric knee extension torque, rate of force development during isometr…
Electromyostimulation Training Effects on Neural Drive and Muscle Architecture
2005
GONDIN, J., M., GUETTE, Y. BALLAY, and A. MARTIN. Electromyostimulation Training Effects on Neural Drive and Muscle Architecture. Med. Sci. Sports Exerc., Vol. 37, No. 8, pp. 1291–1299, 2005. Purpose: The purpose of the study was to investigate the effect of 4 and 8 wk of electromyostimulation (EMS) training on both muscular and neural adaptations of the knee extensor muscles. Methods: Twenty males were divided into the electrostimulated group (EG, N 12) and the control group (CG, N 8). The training program consisted of 32 sessions of isometric EMS over an 8-wk period. All subjects were tested at baseline (B) and retested after 4 (WK4) and 8 (WK8) wk of EMS training. The EMG activity and mu…