Research

Mixed

Thirty-eight days of endurance exercise training significantly attenuates leucine oxidation and branched-chain 2-oxoacid dehydrogenase (BCOAD) activation during moderate-intensity exercise in humans.

If you start an endurance training program, your body becomes more efficient at sparing protein (leucine) during exercise. You do not need to increase your protein intake just because you are exercising more, as long as your intensity is moderate (around 60% VO2 peak). The body adapts by reducing the breakdown of amino acids for energy.

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In conclusion, we found that 38 days of endurance exercise training significantly attenuated both leucine oxidation and BCOAD activation during 90 min of endurance exercise at 60% V˙ O2 peak for both ABS and REL exercise intensities.
S. McKenzie et al. · American Journal of Physiology-Endocrinology and Metabolism · 2000

Why this rating

Randomized controlled trial with isotopic tracing and muscle biopsies, though small sample size (n=12).

Source

Endurance exercise training attenuates leucine oxidation and BCOAD activation during exercise in humans

S. McKenzie et al. · American Journal of Physiology-Endocrinology and Metabolism · 2000

DOI 10.1152/ajpendo.2000.278.4.e580

rct · n=12Cited 217×
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DOI resolved against Crossref · corpus check 2026-06-10

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