Pour les flemmards qui veulent pas aller sur le site de Goundille
Concept déjà développé dans la méthode delavier 2
Association between regional differences in muscle activation in one session of resistance exercise and in muscle hypertrophy after resistance training
Taku Wakahara, Naokazu Miyamoto, Norihide Sugisaki, Koichiro Murata, Hiroaki Kanehisa, Yasuo Kawakami, Tetsuo FukunagaetToshimasa Yanai European Journal of Applied Physiology Volume 112, Number 4 (2012), 1569-1576
The purpose of this study was to examine if the regional difference in muscle hypertrophy after chronic resistance training is associated with muscle activation after one session of resistance exercise. Twelve men performed one session of resistance exercise of elbow extensors. Before and immediately after the exercise, transverse relaxation time (T2)-weighted magnetic resonance (MR) images of upper arm were recorded to evaluate the muscle activation along its length. In the MR images, T2 for the pixels within the triceps brachii muscle was quantified. The number of pixels with T2 greater than the threshold (mean + 1SD of T2 before the exercise) was expressed as the ratio to the number of pixels occupied by the muscle (%activated area). Another 12 subjects completed 12 weeks of training intervention (3 days per week), which consisted of the same program variables as used in the experiment for the T2 measurement. The cross-sectional areas of the triceps brachii before and after the training intervention were measured from MR images of upper arm. The %activated area of the triceps brachii induced by one session of the exercise was found to be significantly lower in the distal region than the middle and proximal regions. Similarly, the relative increase in muscle cross-sectional area after the 12 weeks of training intervention was significantly less in the distal region than the middle and proximal regions. The results suggest that the regional difference in muscle hypertrophy after chronic resistance training is attributable to the regional difference in muscle activation during the exercise.
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Les négatives ne sont pas plus efficaces que les rep positives
13/07/2012
comme on l’a expliqué dans la méthode delavier 2
Similar increases in muscle size and strength in young men after training with maximal shortening or lengthening contractions when matched for total work
Daniel R. Moore, Mark YoungetStuart M. Phillips European Journal of Applied Physiology Volume 112, Number 4 (2012), 1587-1592
Training exclusively with eccentric (lengthening) contractions can result in greater muscular adaptations than training with concentric (shortening) contractions. We aimed to determine whether training-induced increases in muscle size and strength differed between muscles performing maximal lengthening (LC) or maximal shortening (SC) contractions when total external work is equivalent. Nine healthy young males completed a 9-week isokinetic (0.79 rad/s) resistance training program of the elbow flexors whereby they performed LC with one arm and an equivalent volume of total external work with the contralateral arm as SC. Training increased isometric peak torque for both LC (~10%) and SC (~20%) with no difference (P = 0.14) between conditions. There were also similar increases in isokinetic peak torque at both slow (0.79 rad/s) and fast (5.24 rad/s) shortening and lengthening peak torque for both LC (~8–10%) and SC (~9–20%). Training increased work per repetition similarly for both LC (~17%) and SC (~22%), in spite of ~40% greater work per repetition with LC. The increase in muscle cross-sectional area with training was also similar (P = 0.37) between LC (~6.5%) and SC (~4.6%).
We conclude that increases in muscle size and strength with short-term unilateral resistance training are unrelated to muscle contraction type when matched for both exercise intensity (i.e. maximal contractions) and total external work.
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Le travail en endurance réduit les effets de la muscu
13/07/2012
High volume of endurance training impairs adaptations to 12 weeks of strength training in well-trained endurance athletes
Bent R. Rønnestad, Ernst Albin HansenetTruls Raastad European Journal of Applied Physiology Volume 112, Number 4 (2012), 1457-1466,
The purpose of the present study was to compare the effect of 12 weeks of strength training combined with a large volume of endurance training with the effect of strength training alone on the strength training adaptations. Well-trained cyclists with no strength training experience performed heavy strength training twice a week in addition to a high volume of endurance training during a 12-week preparatory period (S + E; n = 11). A group of non-strength trained individuals performed the same strength training as S + E, but without added endurance training (S; n = 7). Thigh muscle cross-sectional area, 1 repetition maximum (1RM) in leg exercises, squat jump performance, and peak rate of force development (RFD) were measured. Following the intervention period, both S + E and S increased 1RM strength, thigh muscle cross-sectional area, and squat jump performance (p < 0.05), and the relative improvements in S were greater than in S + E (p < 0.05). S increased peak RFD while S + E did not, and this improvement was greater than in S + E (p < 0.05). To the best of our knowledge, this is the first controlled study to demonstrate that the strength training response on muscle hypertrophy, 1RM strength, squat jump performance, and peak RFD is attenuated in well-trained endurance athletes during a period of concurrent endurance training.
MOi j'aime bien je trouve ça marrant