Both CONT and WGFE increased isometric knee extensor strength and leg press strength (LP1-RM; primary outcome) during the study period, but there was no difference between groups (p > 0.85, treatment x time).
Secondary analysis of incline leg press strength data showed that baseline strength was inversely correlated with the change in strength by Week 12 in the WGFE group (r = -0.49; P=0.03) but not in the CONT group (r = -0.05; p = 0.80).
At Week 12 there was no difference in pre-exercise mTOR protein phosphorylation ratios between treatments (p = 0.51), but mTOR phosphorylation increased significantly post-exercise in the WGFE group (p < 0.01) but not CONT.
In relation to effects on mRNA expression, in the WGFE group pre-exercise Atrogin-1 gene expression levels at Week 12 were significantly higher than at Week 0 (p < 0.05) and decreased significantly from pre- to post-exercise (-49.7%, p = 0.03).
The main finding of the present study was that supplementation with 1.6 g/day of WGFE during 12 weeks of resistance training in resistance-trained young men did not enhance increases in muscle strength or lean tissue mass.
The magnitude of increase (% increase from baseline) in incline leg press strength in the present study was only ~25-30% of the increase reported in the previous study in untrained men (Carey et al., 2006; Crittenden et al., 2009) which found that WGFE promoted greater increases in strength.
These non-bone lean tissue mass increases, in combination with the small increases observed in thigh girth, suggest that skeletal muscle hypertrophy was induced by the training undertaken, but there was no additional benefit of WGFE supplementation.
However, WGFE supplementation did not significantly alter the response, either at the first exercise session or at the end of the intervention period.
Supplementation with 1.6 g/day of WGFE during resistance exercise training might provide an advantage for increasing strength in untrained individuals (i.e.
* Supplementation with WGFE during resistance training in resistance-trained young men did not enhance increases in muscle strength or lean tissue mass.