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The force-generating capacity measured as isometric torque was markedly reduced (-40-50%) after both exercise bouts. Long lasting recovery indicates muscle damage confirmed by other histological methods. So far only three subjects have been analyzed for MRFs and the preliminary results indicate that the MRF responses are according to our hypothesis. The rest of the samples will be analyzed the next months and the complete results on MRFs and satellite cells will be presented at the congress.
Discussion: In this study, the combination of IHC and Western blotting will give new information about the MRF response after a single bout of muscle damaging eccentric exercise and following a less damaging repeated bout of exercise.
THE EFFECT ON NEUROMUSCULAR JUNCTION FORM AND CONTRACTILE PROPERTIES IN THE RAT SKELETAL MUSCLE
FOLLOWING THE ECCENTRIC CONTRACTION EXERCISE.NISHIZAWA, T., YUKI, A., TAMAKI, H., KASUGA, N., TAKEKURA, H.
CHUKYO WOMEN’S UNIVERCITY JUNIOR NATIONAL INSTITUTE OF FITNESS AND SPORTS, KANOYA, AICHI UNIVERSITY OF
Materials and methods Female Fischer 344/Jcl rats (10 weeks old, body weight, 150–170 g) were used. All procedures in the animal experiments were performed in accordance with the guidelines presented in the Guiding Principles for the Care and Use of Animals in the Field of Physiological Sciences, published by the Physiological Society of Japan.
Training protocol: Downhill training ran on the treadmill continuously for 5min running with 2min rest interval, 18bouts at 40m/min and 16 degree decline. Downhill training it carried out once.
Contraction characteristic: Single muscle fibers were dissected from the extensor digitorum longus (EDL) muscles. Muscle contraction characteristic was measured after eccentric contraction exercise: 1,2,4,8,16,24,60 hours after exercise. The contraction characteristic developed by the nerve stimulation and by the muscle stimulation.
Morphological observation: We observed the degeneration of neuromuscular junctions on the muscle after eccentric-exercise:
1,2,4,8,16,24,60 hours after exercise. Three Types of fibers were classified based on differences ATPase activity. The muscle fiber composition is shown at muscle fiber for different types the number ratio. The morphological observation of neuromuscular junction by optical microscope used cholinesterase and silver staining.
Results: Significant changes in NMJs form occurred in skeletal muscle fibers damaged by eccentric contraction exercise. There was a difference in comparing indirect stimulation tension for the direct stimulation tension after exercise 4 hours. Significant changes was recognized after 16 hours. Significant changes Significant changes of both characteristics appeared after 16 hours. The muscle contraction characteristic was decreased, when the NMJs form is abnormal. It was indicated that the abnormal NMJs form was a factor of the decrease of the muscle contraction force.
EFFECTS OF TENDON VIBRATION ON DISCHARGE BEHAVIOR OF HUMAN MOTOR UNIT DURING SUBMAXIMAL ISOMETRIC CONTRACTIONKAMO, M.
JAPAN WOMEN'S COLLEGE OF PHYSICAL EDUCATIONIntroduction
Discharges of motor units (MU) are well known to show elongating trends in the spike interval during voluntary constant-force isometric contraction (e.g. Kamo, 2002), but neural mechanisms underlying those trends remain unclear. A reduction in Ia afferent activity have been advanced as a possible cause the spike interval elongation (Macefield et al., 1991; Griffin et al., 2001). This study examined effects of manipulation of peripheral afferent by tendon vibration on elongating trends in spike interval of MU during the constant-force contraction.
Methods: Subjects voluntarily performed isometric knee extension with a knee angle of 90 deg at slightly above the recruitment threshold force of the single MU for 60 s (control experiment). Two other situations were used to manipulate (reduce and gain) afferent input by tendon vibration: (1) during the contraction after prolonged vibration (10min), and (2) during the contraction with vibration. The single MU activities in the control experiment, in which there was no intervention, were compared under two experimental situations. Action potentials of single MU were recorded in the vastus medialis muscle using non-invasive surface-array electrodes. Vibratory stimulation was applied perpendicularly to the patella tendon with 75 and 100 Hz frequency and 0.5-0.8 mm displacement.
Results: In the first situation, the spike interval of MUs elongated gradually during contraction, but the amount of the elongation was less than that in control experiment. In the second situation, the spike interval of MUs at the onset of constant-force contraction was significantly longer than that in the control experiment and subsequently shortened to the same interval as that in the control experiment at 30 s, but it began to elongate thereafter.
Discussion: Irrespective of peripheral afferent manipulation, the elongating trend in the spike interval did not disappear during the constant-force contraction. Results suggest that changes in neural input information to single MUs with peripheral afferent stimulation do not eliminate the spike interval’s trend of elongation in the presence of voluntary drive.
References Griffin et al. (2001) J.Physiol., 535, 929-936.
Kamo (2002) Eur. J. Appl. Physiol., 86,375-381.
Macefield et al., (1991) J.Physiol., 440, 497-512.
CHANGES OF REST METABOLIC RATE AND BODY FAT RELATED TO 8 WEEKS WHOLE BODY VIBRATION TRAINING OF
YOUNG FEMALEKUEHNE, T., MISHCHENKO, V.
NEW LIFE BALANCE ACADEMYNew Life Balance GmbH, Roesrath, Germany1 Academy of Physical Education and Sport, Gdansk2 Recent study showed that intensity and duration of aerobic training should be gradually increased so that to maintain the effect of fat oxidation activation in long term health-related physical training. There is a reason to consider strength and whole body vibration training as one of the most perspective types of such training. However, its influence upon energy expenditures and activation of fat losses at rest needs further investigations. The aim was to determine the effects of 8-weeks of mainly strength physical exercises in combination with vibration impacts of inclined type upon rest metabolic rate and fatless body mass, girth of hips as well as cellulite manifestation in young females.
Thirty seven young females aged 20-25 years (students) without any contra-indications took part in the studies. Subjects of experimental group were used vibration platform (VP) LADIES-№1, whereas those of control group performed the same exercises using nonworking VP. One medial-distal complete inclined vibration constituted 0..10 mm at frequency of up to 14 Hz. 24 training sessions (45-55 min) were performed in 8 weeks. Total duration of vibration load at one session constituted 8-12 min. The program of physical exercises designated as ‘vibrobic’ was performed. The exercises preferentially stimulated leg and trunk muscles as well as those of back. After 4 and 8 weeks were measured: rest metabolic rate (VO2), RQ, BMI, fatless body mass (FBM), and girth of two hips.
The results showed that resting oxygen uptake in group of vibration training increased for 8 weeks - from 2,85 (0,15) up to 3,14 (0,13) ml.kg-1.min-1 (p0.05);. resting RQ in 24 hours after last exercises session decreased in the first 4 weeks vibration training only – from 0,841 (0,004) up to 0,819 (0,003) (p0.05). FBM at the end of 8 week trainings was the greater in group of vibration training – 47.30 (2.27) vs 46.73 (2.72) (p0.05), whereas initial values did not differ from control group. In overweight young women only (BMI 25 kg/m2 and higher, n=9) at vibration training took place decrease of BMI (from 26.07 (1.57) up to 24.89 (1.52) kg/m2 ) and % body fat (from 31.4 (1.4) to 29.0 ( 1.5 ) %.
The girth of two hips decreased for 8 weeks in group of vibration training (from 97.8 (3.2) to 96.4 (3.6) sm whereas in control group it did not differ from initial values. Visibility of cellulite of a back surface of two hips in 4 weeks in group of vibration training decreased from 470.4 (35.5) up to 413.4 (29.7) sm2 (p0.05). In control group significant changes were for 8 weeks only.
We concluded that young female special physical training with whole body vibration stimulation induced increasing of rest metabolic rate. The main effects of decreasing in body fat have occurred faster and have been more expressed by the end of training program. It is determined by high potential of vibration stimulation associated with impacts of physical exercises for health-related female training.
INFLUENCE OF THE WHOLE BODY VIBRATION STIMULATION IN THE PROCESS OF HEALTH- RELATED PHYSICAL EXERCISE UPON STRENGTH CAPACITIES OF YOUNG FEMALESMISHCHENKO, V., KUEHNE, T.
NEW LIFE BALANCE ACADEMYAcademy of Physical Education and Sport, Gdansk1 New Life Balance GMBH, Roesrath, Germany2 Introduction. Vibration physical exercises represent a new type of physical exercises the influence of which has been related to the idea of muscle additional stimulation according to mechanism of spinal reflexes (2). Vibration impacts create additional load on neuromuscular apparatus without significant influence upon subjective perception of tension. Meanwhile, application of vibration impacts for the whole body in the course of health-related training of females is somewhat restricted due to insufficient elaboration of the technology of vibration load application in combination with strength exercises. The aim of the study consisted in revealing the effects of 8-weeks mainly strength physical exercises in combination with vibration inclined type for the whole body upon strength capacities and fatless body mass of young females.
Methods. Thirty seven young females aged 20-25 years (students) without any contra-indications took part in the studies. Subjects of experimental group were used vibration platform (VP) LADIES-№1, whereas those of control group performed the same exercises using non-working VP. One medial-distal complete inclined vibration constituted 0..10 mm at frequency of up to 14 Hz. 24 training sessions were performed in 8 weeks. The program of physical exercises designated as VIBROBICA® was performed..Strength type exercises preferentially stimulated leg and trunk muscles as well as those of back. Total duration of vibration load at one session constituted
14 ANNUAL CONGRESS OF THE EUROPEAN COLLEGE OF SPORT SCIENCETH Wednesday, June 24th, 2009 8-12 min. After 4 and 8 weeks were measured: isometric strength (knee extensors); isokinetic strength and strength endurance (feet and arms); explosive strength (in jumps) and jumps endurance (1).
Results. The results showed the special effects of concomitant whole body vibration and physical exercises upon isometric, isokinetic, jumping strength and strength endurance. Augmentation of strength has been observed both in experimental and control group. However, in the group of vibration stimulation these effects have occurred faster and have been more expressed by the end of training program. Mean increasing of feet and arms extensors isokinetic strength for 4 weeks were 9.82 (1.9)% in experimental group meanwhile in control group 5.92 (1.8) for 8 weeks (p0.05). There were no differences of increasing of jump endurance (4.10 vs 3.81%). In group of vibration stimulation strength capacities were increased especially during the first 4 weeks of training and has occurred without any expressed augmentation of active body mass.
Conclusion. We concluded that young female subjected to physical training with whole body vibration stimulation main effects have occurred faster and have been more expressed by the end of training program. The more essential effects were related to maximal and time development of strength and height of jump but not to endurance values.
1.Bosko C. Strength assessment, ISSS, Rome, 1999,165.
2.Torvinen S. et al Clin Physiol Func Im, 2002, 22,p.145-152.
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