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Massage Therapy Attenuates Inflammatory Signaling After Exercise-Induced Muscle Damage
Sci Transl Med 1 February 2012: Vol. 4, Issue 119, p. 119ra13     Justin D. Crane

Massage therapy is commonly used during physical rehabilitation of skeletal muscle to ameliorate pain and promote recovery from injury. Although there is evidence that massage may relieve pain in injured muscle, how massage affects cellular function remains unknown. To assess the effects of massage, we administered either massage therapy or no treatment to separate quadriceps of 11 young male participants after exercise-induced muscle damage. Muscle biopsies were acquired from the quadriceps (vastus lateralis) at baseline, immediately after 10 min of massage treatment, and after a 2.5-hour period of recovery. We found that massage activated the mechanotransduction signaling pathways focal adhesion kinase (FAK) and extracellular signal–regulated kinase 1/2 (ERK1/2), potentiated mitochondrial biogenesis signaling [nuclear peroxisome proliferator–activated receptor γ coactivator 1α (PGC-1α)], and mitigated the rise in nuclear factor κB (NFκB) (p65) nuclear accumulation caused by exercise-induced muscle trauma. Moreover, despite having no effect on muscle metabolites (glycogen, lactate), massage attenuated the production of the inflammatory cytokines tumor necrosis factor–α (TNF-α) and interleukin-6 (IL-6) and reduced heat shock protein 27 (HSP27) phosphorylation, thereby mitigating cellular stress resulting from myofiber injury. In summary, when administered to skeletal muscle that has been acutely damaged through exercise, massage therapy appears to be clinically beneficial by reducing inflammation and promoting mitochondrial biogenesis.

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Pre Vertical Jump Performance to Regulate the Training Volume
Int J Sports Med 2012; 33(02): 101-107   J. G. Claudino

The purpose of this study was to assess the effect of training load regulation, using the CMJ at the beginning of the session, on the total plyometric training load and the vertical jump performance.

44 males were divided into 4 groups:
No Regulation Group (nRG): The nRG received 6 weeks of plyometric training, with no adjustment in training load.
Regulation Group (RG) : The RG underwent the same training; however, the training load was adjusted according to the CMJ performance at the beginning of each session.
Yoked Group (YG) : The adjustment made in RG was replicated for the volunteers from the corresponding quartile in the YG, with no consideration given to the YG participant’s condition at the beginning of its session.
Control Group (CG).

At the end of the training, the CMJ and SJ performance of all of the participants was reassessed. The total training load was significantly lower (p=0.036; ES=0.82) in the RG and the YG (1905±37 jumps) compared to the nRG (1926±0 jumps).

The enhancement in vertical jump performance was significant for the groups that underwent the training (p<0.001).

Vertical jump performance, performed at the beginning of the session, as a tool to regulate the training load resulted in a decrease of the total training load, without decreasing the long-term effects on vertical jump performance.

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Je dirais que c’est plus du super échauffement que de la potentiation

Potentialisation post-effort après un exercice de développé-couché : influence de l’intensité de la pré-activation
Science & Sports   Available online 15 February 2012

Introduction
L’objectif de cette étude est d’explorer les effets aigus d’un travail de développé-couché lourd (trois répétitions à 80 % de la force maximale [Fmax]) et d’un travail de développé-couché léger (quatre répétitions à 20 % de la Fmax) sur la puissance développée à 40 % de la Fmax en développé-couché.

Synthèse des faits
Dix jeunes hommes (20 à 35 ans) entraînés en musculation ont participé à cette étude. Les sujets sont venus à quatre reprises au laboratoire. À la première séance, la Fmax en développé-couché a été mesurée. À la deuxième séance, et après un échauffement standardisé, la puissance à 40 % de la Fmax a été évaluée par un accéléromètre (Myotest Pro) à quatre reprises aux temps suivants : zéro minute, deux minutes, quatre minutes et huit minutes. Lors de la troisième et la quatrième séance, et après le même échauffement, les sujets réalisaient la même séance mais précédée d’une contraction conditionnée légère ou lourde. Les puissances développées à 40 % de la Fmax après le travail de développé-couché léger étaient significativement supérieures à celles développées après le travail lourd et celles réalisées en conditions normales à deux et huit minutes.

Conclusion
Cette étude suggère que les charges légères peuvent induire une meilleure potentialisation post-effort que les charges lourdes lorsqu’elles sont utilisées chez les sujets entraînés en musculation pour le mouvement de développé-couché.

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Pour tous les crétins qui pensent que je ne réponds pas aux questions, cette étude illustre bien le fait qu’un ou un non est une mauvaise réponse
After caffeine ingestion, 11 subjects performed more repetitions, 14 performed fewer repetitions, and 4 performed the same number of repetitions.

No Effects of Caffeine on Muscle Hypertrophy-Style Resistance Exercise
Marius Steiro Fimland and Atle Hole Saeterbakken
Journal of Caffeine Research. June 2011, 1(2): 117-121.

Objective: The purpose of this study was to investigate effects of prior caffeine ingestion on repetitions performed during muscle hypertrophy-style bench press in men and women.

Methods: In a counterbalanced, placebo-controlled, cross-over design, 29 resistance trained men (n=19) and women (n=10) ingested either caffeine (6 mg/kg) or identical placebo pills 1 hour before two experimental sessions. A separate familiarization and one repetition maximum (1-RM) testing session was performed. The experimental sessions consisted of warm-up and six sets of bench press with 70% of 1-RM. Each set was performed until volitional failure and separated by 2-minute rest periods. Repetitions were performed at a constant pace (2 seconds eccentric and 2 seconds concentric).

Results: No effects of caffeine were observed. The total number of repetitions during 6 consecutive sets for men in the caffeine trial was 44±6, and in the placebo trial 44±7. Women performed 51±15 repetitions in the caffeine trial, and 52±19 repetitions in the placebo trial. Men and women combined performed on average 46±10 repetitions in the caffeine trial, and 47±13 repetitions in the placebo trial. After caffeine ingestion, 11 subjects performed more repetitions, 14 performed fewer repetitions, and 4 performed the same number of repetitions.

Conclusions: This study suggests that resistance trained men and women do not benefit from caffeine supplementation before muscle hypertrophy-style bench press.

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The effects of acute alcohol consumption on recovery from a simulated rugby match
Journal of Sports Sciences Volume 30, Issue 3, 2012

In this study, we investigated the effects of acute post-exercise alcohol consumption on measures of physical performance, creatine kinase, and immunoendocrine function in the 48 h following a rugby game simulation. Ten male senior rugby union players completed a rugby game simulation after which they consumed either 1 g of alcohol per kilogram of body mass or a non-alcoholic control beverage. Agility, 15 m sprint, countermovement jump, and srummaging performance were assessed pre-simulation and 24 and 48 h post-simulation. White blood cell count, testosterone, cortisol, and creatine kinase were measured before the simulation and 30 min, 12, 24, 36, and 48 h after the simulation. One week after the first trial, participants completed the second simulation after which the other beverage was consumed. The acute consumption of alcohol after a rugby game simulation negatively affected countermovement jump performance in the days following the simulation (P = 0.028). No differences between treatments were observed for the other criterion measures made in this study. In conclusion, after 80 min of a simulated rugby game, the consumption of 1 g of alcohol per kg body mass negatively impacts lower body vertical power output. However, performance of tasks requiring repeated maximal muscular effort is not affected.

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