The Best Kept Secret for Building Muscle

Study - The Journal of Physiology

We aimed to determine if the time that muscle is under loaded tension during low intensity resistance exercise affects the synthesis of specific muscle protein fractions or phosphorylation of anabolic signalling proteins. Subjects were 8 men (average age of 24) that were habitually active and engaged in lower body resistance exercise at least 2 times per week for more than 2 years at the time of the study. Subjects performed 3 sets of unilateral knee extension exercise at 30% of one-repetition maximum strength involving concentric and eccentric actions that were 6 seconds in duration to failure (SLOW) or a work-matched bout that consisted of concentric and eccentric actions that were 1 second in duration.

(CTL)

Participants ingested 20 g of whey protein immediately after exercise and again at 24 h recovery.

Results

Myofibrillar protein synthetic rate was higher in the SLOW condition versus CTL after 24–30 hours recovery and correlated to p70S6K phosphorylation Exercise-induced rates of mitochondrial and sarcoplasmic protein synthesis were elevated by 114% and 77%, respectively, above rest at 0–6 h post-exercise only in the SLOW condition.

However, mitochondrial protein synthesis rates were elevated above rest during 24–30 h recovery in the SLOW (175%) and CTL (126%) conditions - SLOW was still higher Researchers concluded that greater muscle time under tension increases the acute amplitude of mitochondrial and sarcoplasmic protein synthesis and also results in a robust, but delayed stimulation of myofibrillar protein synthesis 24–30 h after resistance exercise.

The reason that this TUT concept works may be a result of creating a hypoxic environment in the muscles being worked. Hypoxic muscle environments actually enhance muscle strength and hypertrophy - blood flow must be obstructed while time under tension is stressed to create a more anabolic response Increased Muscle Fiber Recruitment A muscle under stress for a longer period of time, stressed to total fatigue, will have greater muscle fiber recruitment In other words, the more time you keep a muscle under tension, the greater chance you have of recruiting fast twitch muscle fibers.