Table 1.
Summary of studies investigating the effect of L-arginine on strength performance.
| Study | Subjects | Design | Intervention | Performance Tests | Main Findings |
|---|---|---|---|---|---|
| Aguiar et al. (2016) [33] | 20 physically active older women (71.6 ± 5.9 y; 61.9 ± 8.6 kg) | Randomized, double-blind, placebo-controlled study | 8 g L-arginine vs. placebo; 80 min prior | 3 sets of 8 maximal isokinetic leg extensions at 60°·s−1 Maximal unilateral isometric force at 60° of knee flexion Sit–stand, tandem gait, and timed up and go functional tests |
↔ isokinetic strength ↔ isometric strength ↔ functional tests ↔ femoral artery vasodilation |
| Álvares et al. (2012) [30] | 15 recreationally trained men (26.3 ± 4.9 y; 79.2 ± 13.4 kg) | Randomized, double-blind, placebo-controlled study | 6 g L-arginine vs. placebo; 80 min prior | 3 sets of 10 maximal isokinetic elbow extensions at 60°·s−1 | ↔ isokinetic strength ↔ NOx |
| Andrade et al. (2018) [44] | 20 recreationally active men and women (23.0 ± 4.0 y; 71.2 ± 8.3 kg) | Randomized, double-blind, placebo-controlled study | 6 g L-arginine vs. placebo; 60 min prior | 3 sets of 8–12 leg press and hack squat (70% 1RM) 1 set of leg press (60% 1RM) to failure performed at 24, 48, and 72 h post |
↔ repetitions to failure ↔ surface EMG ↔ creatine kinase ↔ lactate ↔ testosterone:cortisol ratio ↔ muscle soreness |
| Campbell et al. (2006) [40] | 35 resistance trained men (38.9 ± 5.8 y; 86.0 ± 13.7 kg) | Randomized, double-blind, placebo-controlled study | 12 g L-arginine α-ketoglutarate (1:1 ratio) vs. placebo; daily for 8 weeks during periodized resistance training | 1RM bench press Isokinetic leg extension endurance test 30 s WAnT Aerobic capacity test Body composition |
↑ 1RM bench press ↔ isokinetic endurance ↑ peak WAnT power ↔ aerobic capacity ↔ body composition |
| Fahs et al. (2009) [34] | 18 healthy men (24.2 ± 0.7 y; 86.7 ± 4.9 kg) | Randomized, double-blind, placebo-controlled, crossover study | 7 g L-arginine vs. placebo; 30 min prior | 4 sets of 5 bench press (80% 1RM) 4 sets of 10 biceps curl (70% 1RM) |
↔ forearm blood flow ↔ arterial stiffness |
| Greer & Jones (2011) [39] | 12 resistance-trained men (22.6 ± 3.8 y; 12.1 ± 4.1% body fat) | Randomized, double-blind, placebo-controlled, crossover study | 3.7 g L-arginine α-ketoglutarate vs. placebo; 4 h and 30 min prior | 3 sets of chin-ups, reverse chin-ups, and push-ups to failure | ↓ repetitions to failure |
| Liu et al. (2009) [31] | 10 elite judo athletes (20.2 ± 0.6 y; 73.3 ± 2.1 kg) | Randomized, double-blind, placebo-controlled, crossover study | 6 g L-arginine vs. placebo; 3 days (60 min prior) | Intermittent anaerobic exercise test | ↔ peak power ↔ average power ↑ arginine concentrations ↔ NO x↔ lactate ↔ ammonia |
| Meirellas & Matsuura (2018) [32] | 12 recreationally resistance-trained men (27 ± 3 y; 77 ± 8 kg) | Randomized, double-blind, placebo-controlled, crossover study | 6 g L-arginine vs. placebo; 60 min prior | 3 sets of bench press (70% 1RM) to failure 3 sets knee extensions (80% 1RM) to failure |
↔ repetitions to failure ↔ NOx |
| Olek et al. (2010) [37] | 6 physically active men (23.2 ± 0.5 y; 84.0 ± 2.5 kg) | Randomized, double-blind, placebo-controlled, crossover study | 6 g L-arginine vs. placebo; 60 min prior | 3 30 s WAnT | ↔ WAnT performance ↔ lactate ↔ ammonia |
| Santos et al. (2002) [36] | 12 inactive men (23.8 ± 3.5 y; 75.8 ± 12.1 kg) | Non-randomized, non-placebo- controlled study | 3 g L-arginine for 15 days; 60 min prior | 15 maximal isokinetic leg extensions at 180°·s−1 | ↓ work fatigue index |
| Tang et al. (2011) [35] | 8 recreationally active men (22.1 ± 2.6 y; 76.6 ± 6.2 kg) | Randomized, double-blind, crossover study | 10 g of essential amino acids with 10 g of L-arginine vs. isonitrogenous control; post-exercise | Unilateral seated leg press and knee extension exercises | ↔ NO synthesis ↔ muscle blood flow ↔ muscle protein synthesis |
| Wax et al. (2013) [38] | 19 recreationally active men (19.4 ± 1.3 y; 79.2 ± 10.6 kg) | Randomized, double-blind, placebo-controlled, crossover study | 3 g L-arginine α-ketoglutarate vs. placebo; 45 min prior | 1RM bench press and leg press 1 set of bench press and leg press (60% 1RM) to failure |
↔ 1RM strength ↔ repetitions to fatigue |
↑ = significantly greater (p < 0.05) than placebo; ↓ = significantly less (p < 0.05) than placebo; ↔ = no significant difference between supplement and placebo; 1RM = one-repetition maximum; EMG = electromyography; NOx = nitrite and nitrate; WAnT = Wingate anaerobic.