Omega-3 fatty acid supplementation attenuates skeletal muscle disuse atrophy during two weeks of unilateral leg immobilization in healthy young women.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 30629458 · doi:10.1096/fj.201801857RRR
What was done
Twenty healthy young women (mean age 22 ± 3 years, BMI 23.0 ± 2.3 kg/m²) were randomized to consume either 5 g/day of omega-3 fatty acids or an isoenergetic sunflower oil control. Supplementation began 4 weeks prior to a 2-week period of unilateral leg immobilization, followed by a 2-week recovery period of normal activity. Muscle size and mass were assessed pre-immobilization, post-immobilization, and post-recovery, alongside serial muscle biopsies to measure integrated daily myofibrillar protein synthesis (MyoPS).
What was found
Following 2 weeks of immobilization, skeletal muscle volume decreased significantly more in the control group than in the omega-3 group (14% vs. 8%, P < 0.05). Muscle mass was significantly reduced post-immobilization in the control group only (P < 0.05). After 2 weeks of recovery, muscle volume in the omega-3 group returned to baseline, whereas it remained significantly lower in the control group (P < 0.05). Integrated MyoPS was higher in the omega-3 group compared with the control group at all time points (P < 0.05).
Why it matters
Omega-3 supplementation appears to mitigate disuse-induced skeletal muscle atrophy and facilitate recovery, likely via sustained elevations in muscle protein synthesis. This provides a potential nutritional strategy to preserve muscle mass during acute periods of limb immobilization or physical inactivity.
Limits
The study is limited by a small sample size (n = 20) and included only healthy, young female participants, preventing direct generalization to males, older adults, or clinical populations facing prolonged bed rest. In addition, the dose tested (5 g/day) is relatively high, and the abstract does not report functional strength outcomes.
Cited by
- supports In a study by Chris McGlory and Stuart Phillips, preloading young women with 5 grams per day of omega-3 for 4 weeks before single-leg immobilization reduced disuse muscle atrophy by 50%.