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Background. Aging is associated with greater susceptibility to muscle injury and soreness after exercise. Although elderly persons regularly consume nonsteroidal anti-inflammatory drugs (NSAIDs), it is not clear that NSAIDs alleviate muscle dysfunction and/or inflammation following injurious exercise. Methods. In this double-blind crossover study, 10 men and 5 women (aged 60 � 2 years, meanSE ) consumed naproxen sodium or placebo for 10 days after performing 64 unilateral eccentric (ECC) knee extensions using 75% of the ECC 1-repetition maximum. Strength was measured before, 3 days after, and 10 days after each bout. Injury and soreness were assessed using magnetic resonance images of m. quadriceps femoris (QF) and a visual analog scale. Results. Three days after exercise, concentric strength loss was greater for placebo ( � 32 � 9%) than NSAID ( � 6 � 8%; p � .0064). Likewise, isometric strength declined less for NSAID than placebo ( � 12 � 7% vs � 24 � 4%; p � .0213), and thigh soreness while rising from a chair was greater for placebo ( p � .0393) than NSAID (43 � 7 mm vs 26 � 7 mm). QF cross-sectional area (cm 2 ) showing elevated T 2 was 27% and 35% greater ( p � .0096) for placebo on Days 3 and 10, respectively. Conclusions. Naproxen sodium attenuated muscle injury, strength loss, and soreness following ECC exercise in older individuals and may be beneficial during the early stages of increased physical activity.

We tested the null hypothesis that creatine monohydrate loading (20 g per day for 7 days, n = 18) would not alter resistance exercise performance, isometric strength, or in vivo contractile properties of the quadriceps femoris muscle compared with loading with placebo (n = 13) in resistance-trained subjects. For the entire study group, the 1 repetition maximum (1RM) and 5-set performance (the number of repetitions) for unilateral, dynamic knee extension increased slightly (2% and 5%, respectively) after dietary supplementation, and these responses did not differ by condition. Maximal voluntary isometric torque and the rate of torque development did not change. During electromyostimulation, torque development and relaxation time were also unaffected. Our data suggest that creatine loading does not augment unilateral strength or multiset resistance exercise performance for knee extensions compared with placebo loading.

This study examined the influence of dietary creatine (CR) supplementation upon mechanical and hypertrophic responses to a well-defined conditioning stimulus provided by electromyostimulation (EMS).Eighteen resistance-trained subjects were assigned CR or a placebo (PL) in a randomized, double-blind fashion. After CR loading (20 g x d(-1) for 7 d), CR supplementation (5 g x d(-1)) or PL was continued for 8 wk. During supplementation, EMS (3--5 sets of 10 coupled eccentric and concentric actions) was applied to the left m. quadriceps femoris (QF) twice weekly while subjects continued voluntary resistance training of both lower limbs unsupervised. Cross-sectional area (CSA) of each QF was assessed with magnetic resonance imaging (MRI). Torque during EMS was analyzed to assess muscle loading and fatigue resistance.Maximal torque and the torque time integral increased markedly over training (Por = 0.0001). These responses reflected activation of more muscle as EMS current was increased (about 16%), greater recovery between sets (Por = 0.0423), and less fatigue during sets over training (P = 0.0002). CR did not influence these responses (P = 0.8093). In accord with these results, the increase in CSA for the stimulated QF (11%) was comparable for CR and PL (P = 0.2190). CSA in the nonstimulated QF increased 5% in CR (P = 0.0091) but did not change in PL.We conclude that CR supplementation did not augment the mechanical or hypertrophic response to a precisely measured conditioning stimulus that attenuated but did not ameliorate fatigue. We suggest that enhanced fatigue resistance may not explain the apparent ergogenic effect of CR during voluntary training.