Radar des Essais Cliniques

Fiber type-specific cell signalling

This measure will be investigated during an experimental trial in which the participants are subjected to an acute bout of resistance exercise followed by the ingestion of essential amino acids (240 mg/kg lean mass). During this 3 hour time period, the participants will donate two muscle biopsies, one before exercise and the second one 1 hour after exercise. Cell signalling networks related to muscle mass regulation will be examined in these biopsy samples. The signal will be measured using Western blotting and the signal obtained is expressed in relation to baseline (adjusted volume intensity).

1 hour after ingestion of essential amino acids and resistance exercise

Skeletal muscle fiber characteristics

Fiber type-specific area measured using immunofluorescence microscope in muscle biopsies collected at baseline (prior to ingestion of essential amino acids and resistance exercise). Unit of measurement is square micrometers (µm\^2).

1 hour prior to ingestion of essential amino acids and resistance exercise

Whole body muscle volume

Indices of muscle volume and fat infiltration obtained with magnetic resonance imaging (MRI). Unit of measurement is cubic centrimeters (cm\^3).

1 hour

Whole body glucose tolerance

Oral glucose tolerance test in which the participants will ingest a standardized glucose drink and blood glucose levels will be monitored throughout a period of 2 hours. Unit of measurement is mmol/L glucose.

2 hours

Accelerometer-assessed physical activity levels

Hip-worn accelerometer data (Actigraph GT3X) collected over 7 consecutive days. Unit of measurement is steps per day.

1 week

Isometric and isokinetic leg muscle strength

Muscle performance will be evaluated at a single timepoint during the study using IsoMed2000 dynamometer. Participants will perform a maximal isometric contraction at 60 degrees of knee flexion. Unit of measurement is Newton meter (N-m).

1 hour