Influence of Omega‐6 HUFA Status on Recovery of Muscle Performance After Fatiguing Exercise

Abstract

High %n‐6 HUFA in plasma and tissues is associated with a heightened inflammatory response.PURPOSETo test if a diet that lowers the %n‐6 would be associated with less strength loss after fatiguing load carriage exercise and shorter time to recover muscle strength and performance.METHODSVolunteers were randomly assigned to either a control diet (CON; n=23; 22.5 g n‐6 and 0.2 g n‐3 HUFA/2,000 kcal) plus placebo smoothie (‐S), an experimental diet (EXP; n=25; 8.0 g n‐6 and 0.9 g n‐3 HUFA/2,000 kcal) and ‐S, or EXP plus n‐3 fortified smoothie (EXP+S; n=23; 1.9 g n‐3 HUFA) for 10 weeks. Volunteers performed a single leg step test (up to 3 sets & 6 min each leg) while wearing a 20 kg vest. Maximal isometric and isokinetic torque at 60°/sec, and total work during 20 reps at 180°/sec were measured before, 5 min after the step test, and 24, 48 and 72 h of recovery.RESULTSThe step test produced a 20% (95%CI 16‐25), 19% (12‐25), and 19% (15‐27) reduction in isometric torque for EXP+S, EXP‐S, and CON, respectively, with no group x time interaction during recovery (p=0.89). A similar magnitude and pattern was observed for isokinetic torque and total work.CONCLUSIONA 10‐wk dietary manipulation that substantially lowered %n‐6 and increased %n‐3 HUFA was not associated with less fatigue or faster recovery after load carriage exercise. The views expressed in this abstract are those of the authors and do not reflect the official policy of the Dept. Army, Dept. Defense, or the U.S. Government.