author={Jared W. Coburn and Dona J. Housh and Terry J. Housh and Moh H. Malek and Travis W. Beck and Joel T. Cramer and Glen O. Johnson and Patrick E. Donlin},
  journal={Journal of Strength and Conditioning Research},
The purpose of this study was to determine the effects of resistance training in combination with a leucine and whey protein supplement or a carbohydrate placebo on strength and muscle cross-sectional area (CSA). Thirty-three men (mean age ± SD = 22.4 ± 2.4 years) were assigned to 1 of 3 groups: (1) supplementation group (SUPP), (2) placebo group (PL), or (3) control group (CON). The SUPP and PL performed unilateral training of the leg extensor muscles with the nondominant limb for 8 weeks. The… 

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The effects of leucine and whey protein supplementation with eight weeks of resistance training on strength and body composition.

Whey protein supplementation in male collegiate athletes during resistance training achieved greater increase in strength than leucine and placebo groups, and leucines group achieved significantly greater improvement in body composition than whey protein and placebo group.

The Effects of Whey Protein Supplementation on Performance and Hormonal Adaptations Following Resistance Training in Novice Men

It can, therefore, be concluded that within 8 weeks whey protein supplementation was found to increase explosive muscular power, body weight and muscle strength.

Free leucine supplementation during an 8-week resistance training program does not increase muscle mass and strength in untrained young adult subjects

Free leucine supplementation does not increase muscle strength or CSA during RT in healthy young subjects consuming adequate dietary protein intake.

Muscle strength and hypertrophy occur independently of protein supplementation during short-term resistance training in untrained men.

It is suggested that short-term resistance training augments muscle strength and size in previously untrained men with no additive benefit from postexercise protein supplementation.

The Effects of Leucine or Different Protein Supplements on Muscle Hypertrophy after 12 Weeks of Resistance Training in Untrained Men

All supplement groups exhibited similar training volumes and experienced statistically similar increases in total body skeletal muscle mass determined by dual x-ray absorptiometry, as well as increasing Calorie intakes from T1 to T39.

The effects of 8 weeks of heavy resistance training and branched-chain amino acid supplementation on body composition and muscle performance

When combined with heavy resistance training for 8 weeks, supplementation with 9 g/day of BCAA 30 min before and after exercise had no preferential effects on body composition and muscle performance.

Effect of Leucine Supplementation on Indices of Muscle Damage and Recovery Following Eccentric-Based Resistance Exercise

Leucine supplementation minimized the decrement in muscle function and maintained force output when compared to a placebo and may facilitate the recovery process.

The influence of 8 weeks of whey-protein and leucine supplementation on physical and cognitive performance.

It is concluded that supplementing with whey protein and leucine may provide an advantage to people whose performance benefits from increased upper body strength and/or lean body mass.

Daily L-leucine supplementation in novice trainees during a 12-week weight training program.

It is suggested that 4 g/d of L-leucine supplementation may be used as a nutritional supplement to enhance strength performance during a 12-week resistance training program of initially untrained male participants.

Effects of Insect Protein Supplementation during Resistance Training on Changes in Muscle Mass and Strength in Young Men

In young healthy men, insect protein supplementation did not improve adaptations to eight weeks of resistance training in comparison to carbohydrate supplementation, and a high habitual protein intake in both Con and Pro may partly explain the observation of no superior effect.



The Effects of Amino Acid Supplementation on Muscular Performance During Resistance Training Overreaching

The results indicate that the initial impact of high-volume resistance training overreaching reduces muscle strength and power, and it appears that these reductions are attenuated with amino acid supplementation, and an initial high- volume, moderate-intensity phase of overreaching followed by a higher intensity, moderate volume phase appears to be very effective for enhancing muscle strength in resistance-trained men.

Leucine supplementation and serum amino acids, testosterone, cortisol and growth hormone in male power athletes during training.

The present findings indicate that on a daily protein intake of 1.26 g/kg body weight the serum concentrations of amino acids are lowered considerably and earlier than the decrease in the serum testosterone concentration during the training season in adult male power athletes.

Is glucose/amino acid supplementation after exercise an aid to strength training?

Regular glucose/amino acid supplementation immediately after resistance exercise is unlikely to enhance the gain in muscle strength brought about by resistance training.

Oral amino-acid provision does not affect muscle strength or size gains in older men.

It is suggested that whole muscle strength and size are not enhanced with a postexercise daily provision of an oral amino-acid complex during 12 wk of PRT in older men.

Essential amino acids and muscle protein recovery from resistance exercise.

It is concluded that NEAA are not necessary for stimulation of NB and that there is a dose-dependent effect of EAA ingestion on muscle protein synthesis.

Leucine Supplementation and Intensive Training

According to 1 study, dietary supplementation of the leucine metabolite β-hydroxy-β-methylbutyrate 3 g/day to humans undertaking intensive resistance training exercise resulted in an increased deposition of fat-free mass and an accompanying increase in strength.

An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise.

It is concluded that essential amino acids with carbohydrates stimulate muscle protein anabolism by increasing muscle protein synthesis when ingested 1 or 3 h after resistance exercise.