Search results for " Strength"
showing 10 items of 1999 documents
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…
Effects of strength vs. endurance training and their combination on physical performance characteristics in female horseback riders
2020
BACKGROUND: The purpose of this study was to investigate effects of strength (S), endurance (E) and concurrent strength and endurance (SE) training on neuromuscular and cardiorespiratory characteristics during the 12-week volume-equated protocols in female horseback riders. METHODS: Subjects (N=44) (29.4±8.9 yrs) were assigned to S (n=11), E (n=11), SE (n=13) and control (C) (n=9) groups. Training consisted of progressive S, E or SE training 3x/week and riding exercise 4-6x/week. The measurements included maximal isometric bilateral leg press force (MVCLP) and EMG of VL and BF muscles, rapid isometric force production (0-500ms), maximal force of trunk extensor/flexors (MVCE/MVCF), countermo…
Deadlift muscle force and activation under stable and unstable conditions.
2010
The objective of this study was to compare the production of force and paraspinal muscle activity between deadlifts carried out in a standard way and with different instability devices (Bosu and T-Bow). Deadlifts involve the performance of muscle activities with dynamic and isometric characteristics. Thirty-one subjects participated voluntarily in the study. Initially, they performed an isometric test for 5 seconds in each condition. After that, they performed a set of 5 repetitions with 70% of the maximum isometric force obtained in each one of the previously evaluated conditions. During the isometric tests, records of electromyographic activity and force production were obtained, whereas …
Effective Henry's law partitioning and the salting constant of glyoxal in aerosols containing sulfate.
2013
The reversible partitioning of glyoxal was studied in simulation chamber experiments for the first time by time-resolved measurements of gas-phase and particle-phase concentrations in sulfate-containing aerosols. Two complementary methods for the measurement of glyoxal particle-phase concentrations are compared: (1) an offline method utilizing filter sampling of chamber aerosols followed by HPLC-MS/MS analysis and (2) positive matrix factorization (PMF) analysis of aerosol mass spectrometer (AMS) data. Ammonium sulfate (AS) and internally mixed ammonium sulfate/fulvic acid (AS/FA) seed aerosols both show an exponential increase of effective Henry's law coefficients (KH,eff) with AS concentr…
Thresholds of handgrip strength for all-cause, cancer, and cardiovascular mortality: A systematic review with dose-response meta-analysis.
2022
Background While handgrip strength is associated with all-cause and cause-specific mortality, whether such associations are dose-dependent is largely unknown. Therefore, we conducted a systematic review on the dose-response relationship of handgrip strength with all-cause mortality, cancer, and cardiovascular mortality. Methods The data source included three electronic databases (PubMed/MEDLINE, Web of Science and Scopus) from inception to 8 February 2022. Prospective cohort studies of healthy adults with objective measures of handgrip strength were included. Two researchers independently screened studies, extracted data, and assessed risk of bias. We used estimates regarding handgrip stren…
An investigation of the mechanical properties of rubber modified asphalt mixtures using a modified dry process
2017
Incorporating recycling tyres into asphalt mixtures contributes to solving a serious environmental problem as well as the potential of improving the mechanical performance of asphalt mixtures. The recycled tyre rubber is added by two technologies known as the dry process (when rubber particles are treated as an aggregate modifier) and the wet process (when rubber particles are treated as a binder modifier). Although, the dry process is easier and requires minimal or no modification in the asphalt plant, the inconsistency in field performance makes the dry process not widely used. The main reason for this is believed to be the lack of interaction between the rubber particles and binder. In o…
An aggression machine v. determinants in reactive aggression revisited
2001
The relations between reactive aggression, situational cues, and emotion regulation were examined by means of the Pulkkinen Aggression Machine (PAM) task. In the PAM, provocation and response were systematically varied under two conditions: the impulsive aggression condition and the controlled aggression condition. In the impulsive condition, no information about the attacker was provided, while in the controlled condition the attackers were specified in terms of sex, age, and physical strength. The task was administered to 109 children aged 8 to 13 years. Boys (n = 61) and girls (n = 48), as well as subgroups of Adjusted (n = 67) and Maladjusted (n = 26) children were compared. The results…
Biological clocks and physical functioning in monozygotic female twins
2018
Background Biomarkers of biological aging – DNA methylation age (DNAm age) and leukocyte telomere length (LTL)– correlate strongly with chronological age across the life course. It is, however, unclear how these measures of cellular wear and tear are associated with muscle strength and functional capacity, which are known to decline with older age and are associated with mortality. We investigated if DNAm age and LTL were associated with body composition and physical functioning by examining 48 monozygotic twin sisters. Methods White blood cell DNAm age (predicted years) was calculated from Illumina 450 k BeadChip methylation data using an online calculator. DNAm age acceleration was define…
Update on the ESCEO recommendation for the conduct of clinical trials for drugs aiming at the treatment of sarcopenia in older adults
2020
Abstract Background In 2016, an expert working group was convened under the auspices of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) and formulated consensus recommendations for the conduct of clinical trials for drugs to prevent or treat sarcopenia. Aims The objective of the current paper is to provide a 2020 update of the previous recommendations in accordance with the evidence that has become available since our original recommendations. Methods This paper is based on literature reviews performed by members of the ESCEO working group and followed up with face to face meetings organized for the whole group to make amendments and discuss…