Wednesday, February 18, 2009

Performance Research for February: Protein Synthesis Round 2

Even more data for all you on how to stay "functional" and add muscle.

Off to the U of MN for some early morning testing on subject in my Energy Drink study.

Aging, exercise and muscle protein metabolism.

Koopman R, van Loon LJ. NUTRIM, Maastricht University.

Aging is accompanied by a progressive loss of skeletal muscle mass and strength, leading to the loss of functional capacity and an increased risk of developing chronic metabolic disease. The age-related loss of skeletal muscle mass is attributed to a disruption in the regulation of skeletal muscle protein turnover, resulting in an imbalance between muscle protein synthesis and degradation. As basal (fasting) muscle protein synthesis rates do not seem to differ substantially between the young and elderly, many research groups have started to focus on the muscle protein synthetic response to the main anabolic stimuli, i.e. food intake and physical activity. Recent studies suggest that the muscle protein synthetic response to food intake is blunted in the elderly.

The latter is now believed to represent a key factor responsible for the age-related decline in skeletal muscle mass. Physical activity and/or exercise stimulate post-exercise muscle protein accretion in both the young and elderly. However, the latter largely depends on the timed administration of amino acids and/or protein prior to, during, and/or after exercise. Prolonged resistance type exercise training represents an effective therapeutic strategy to augment skeletal muscle mass and improve functional performance in the elderly. The latter shows that the ability of the muscle protein synthetic machinery to respond to anabolic stimuli is preserved up to very old age.

CONCLUSION: Research is warranted to elucidate the interaction between nutrition, exercise and the skeletal muscle adaptive response. The latter is needed to define more effective strategies that will maximize the therapeutic benefits of lifestyle intervention in the elderly.

My Notes: A very astute reader of my newsletter (seriously, I would put the average IQ of my newsletter readers up against anyone in an IQ Battle and day of the week), pointed out that in my previous blog (see link below) that the response of protein in older athletes is not the same. He was exactly correct and this is a great review of what may be going on.

Research Review: Do You Only Need 20 Grams of Protein Post Workout?

As you age, you really want to keep as much muscle as possible since it is muscle/strength that allows you to function on a day to day basis and enjoy a higher quality of life.

Differential stimulation of myofibrillar and sarcoplasmic protein synthesis with protein ingestion at rest and after resistance exercise.

Moore DR, Tang JE, Burd NA, Rerecich T, Tarnopolsky MA, Phillips SM. McMaster University.

We aimed to determine whether there is a differential stimulation of the contractile myofibrillar and the cellular sarcoplasmic proteins after ingestion of protein and how this is affected by resistance exercise. Fasted (FAST) muscle protein synthesis was measured in seven healthy young men with a primed constant infusion of L-[ring-(13)C6]phenylalanine. Participants then performed an intense bout of unilateral resistance exercise followed by the consumption of 25 g of whey protein to maximally stimulate protein synthesis. In the rested (FED) leg myofibrillar (MYO) protein synthesis was elevated (P<0.01)>0.05).

In contrast, MYO protein synthesis in the exercised (FED-EX) leg was stimulated above FAST at 1, 3, and 5 h (~100, 216, and 229%, respectively; P<0.01) style="font-weight: bold;">he synthesis of muscle contractile proteins is stimulated by both feeding and resistance exercise early (1 h) but is still elevated at 5h after resistance exercise. In contrast, sarcoplasmic (SARC) protein synthesis was similarly elevated (P<0.01) style="font-weight: bold;">

CONCLUSION: In conclusion, myofibrillar and sarcoplasmic protein synthesis are similarly, but transiently, stimulated with protein feeding. In contrast, resistance exercise rapidly stimulates and sustains the synthesis of only the myofibrillar protein fraction after protein ingestion. These data highlight the importance of measuring the synthetic response of specific muscle protein fractions when examining the effects of exercise and nutrition.

My notes: Interesting to note that it was still elevated at 5 hours, but 5 hours was the last measurement they took, so it could be going on even longer. Keep this in mind the next time you hear that the 'anabolic window is only 2 hours long'

Maximizing muscle protein anabolism: the role of protein quality.

Tang JE, Phillips SM. Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada.

PURPOSE OF REVIEW: Muscle protein synthesis (MPS) and muscle protein breakdown are simultaneous ongoing processes. Here, we examine evidence for how protein quality can affect exercise-induced muscle protein anabolism or protein balance (MPS minus muscle protein breakdown). Evidence is highlighted showing differences in the responses of MPS, and muscle protein accretion, with ingestion of milk-based and soy-based proteins in young and elderly persons.

RECENT FINDINGS: Protein consumption, and the accompanying hyperaminoacidemia, stimulates an increase in MPS and a small suppression of muscle protein breakdown.

Beyond the feeding-induced rise in MPS, small incremental addition of new muscle protein mass occurs following intense resistance exercise which over time (i.e. resistance training) leads to muscle hypertrophy. Athletes make use of the paradigm of resistance training and eating to maximize the gains in their skeletal muscle mass. Importantly, however, metabolically active skeletal muscle can offset the morbidities associated with the sarcopenia of aging such as type II diabetes, decline in aerobic fitness and the reduction in metabolic rate that can lead to fat mass accumulation.

CONCLUSION: Recent evidence suggests that consumption of different proteins can affect the amplitude and possibly duration of MPS increases after feeding and this effect interacts and is possibly accentuated with resistance exercise.

My Notes: Wow, they are cranking out the killer studies up in Canada there eh! So the type of protein you take in appears to affect the response. While still debatable, I would go with a high quality whey protein per and post training (about 20-40 grams).