| 1. |
- Folkesson, Mattias, et al.
(författare)
-
Immunohistochemical changes in the expression of HSP27 in exercised human vastus lateralis muscle
- 2008
-
Ingår i: Acta Physiologica. - 1748-1708. ; 194:3, s. 215-222
-
Tidskriftsartikel (refereegranskat)abstract
- AIM: The role of HSP27 in the adaptive process of skeletal muscle to exercise, especially in humans, is not well understood. The objective of this study was to investigate immunohistochemical changes in HSP27 expression in human vastus lateralis muscle following resistance and endurance exercises.METHODS: Two different exercise protocols were used: (1) one-leg ergometer cycling (EC, n = 6) consisting of two 30-min bouts at 40% and 75% of peak oxygen uptake, respectively, and (2) leg extension resistance exercise (RE, n = 9) including 10 sets of eight repetitions at a load corresponding to 70% of one maximal repetition (1RM). Immunohistochemistry using specific monoclonal antibodies was used to determine the location of HSP27 protein in muscle biopsies from human vastus lateralis.RESULTS: Our results show that RE, but not EC, induced a significant appearance of scattered accumulations of HSP27 protein in muscle fibres from five of nine subjects. The number of fibres with accumulation of HSP27 in RE ranged from 0% to 32% with a mean of 6.3% of the total number of fibres.CONCLUSION: We conclude that this rapid HSP27 protein relocation after RE is an important player in the cellular remodelling of human muscle fibres in response to exercise involving high-force contractions, but not in response to endurance exercises.
|
|
| 2. |
- Kadi, Fawzi, et al.
(författare)
-
Strength, muscular endurance and EMG characteristics of thigh adductors
- 2006
-
Ingår i: Isokinetics and exercise science. - 0959-3020. ; 14:3, s. 235-239
-
Tidskriftsartikel (refereegranskat)abstract
- The assessment of thigh adductors' strength and endurance and electromyographical (EMG) characteristics has received little attention compared to other muscle groups. The aim of this study was to investigate strength, endurance performance and EMG characteristics of m. adductor longus and m. gracilis during concentric thigh adduction in soccer and bandy players. Muscular endurance was evaluated using the torque reduction during 70 repeated maximum concentric adductions at an angular velocity of 60°/s. The EMG mean frequency (MNF) and the signal amplitude ratio (SAR, index for muscles' ability to relax between contractions) were analysed. Peak torque decreased significantly throughout the test and no significant differences were found between the two groups. In both muscles, MNF decreased significantly throughout the test. There were no significant differences in MNF and in SAR variables between soccer and bandy players. In conclusion, the present findings reveal a number of significant aspects related to strength and electromyography of hip adductors. © 2006 - IOS Press and the authors. All rights reserved.
|
|
