Nocturnal muscle protein synthesis after neuromuscular electrical stimulation in elderly men.

Rationale:

With human aging there is a gradual but progressive decline in skeletal muscle mass, termed sarcopenia. While the underlying cause of sarcopenia is likely to be multifaceted, a primary factor is that elderly individuals frequently experience short periods of muscle disuse following limb immobilization or bed-rest (due to injury or illness) causing rapid muscle loss. Feasible strategies for maintaining muscle protein synthesis rates in elderly individuals, and thus having the potential to attenuate the loss of muscle mass during disuse need to be pursued. Local neuromuscular electrical stimulation (NMES) in combination with additional intake of protein offer such a potential strategy but, as yet, remains relatively unexplored.



Objective:

To test the hypothesis that ingesting a nocturnal bolus of protein in combination with NMES stimulates muscle protein synthesis in elderly more than ingesting protein without NMES.



Study design:

Prospective, single blind, intervention study.



Intervention:

Consumption of a 40 g bolus of intrinsically L[1-13C]-phenylalanine labeled casein protein and 70 min of one-legged NMES.



Endpoints:

Enrichments of muscle tissue after ingestion of an [1-13C]-phenylalanine intrinsically labeled casein drink.

Is overnight incorporation of [1-13C]-phenylalanine amino acids higher in muscle tissue in combination with NMES than in unstimulated skeletal muscle?

Overnight (i.e. the morning after ingestion of the stable isotope drink and NMES). Method of measurement is massaspectrometry.

Consumption of a 40 g bolus of intrinsically L[1-13C]-phenylalanine labeled casein protein and 70 min of one-legged NMES.