Alpha-GPC supplementation linked to improved strength in new clinical study
Researchers from the University of Louisiana at Lafayette found that, compared to participants taking a placebo, participants supplemented with 250 mg of A-GPC, a molecule in the choline synthesis pathway, demonstrated the greatest improvement in performing a counter-movement jump.
“It can be suggested that athletes and coaches looking to improve performance in events that emphasize velocity and power consider adding A-GPC to their nutritional strategy,” the researchers wrote in their study, published in the Journal of the International Society of Sports Nutrition.
The researchers were led by Dr David Bellar, an assistant professor in the university's School of Kinesiology. He also authored the most recent study on A-GPC prior to this current one, published in 2015, which suggested that the molecule may boost lower body force production in only six days of supplementation.
The participants were 48 healthy college-aged males recruited from the university, representing a “convenience sample of recreationally trained subjects.”
After an overnight fast, the participants’ body measurements were collected and an assessment of three exercise moves (counter-movement jump, isometric mid-thigh pull, and upper body isometric test) was conducted.
Participants were assigned to one of four groups: A 500 mg A-GPC group, 250 mg A-GPC group, a 200 mg caffeine group, or placebo of microcrystalline cellulose, all in capsule form. All capsules were provided by Austin, TX-based Chemi Nutra, and their contents verified by an independent lab
The first dose was given with cool water, after which the participants sat quietly for 120 minutes. At 60 minutes and 120 minutes after ingestion, blood samples were collected.
Then, the participants were given the capsules to take home and consume twice a day in the next six days. On the final intervention day, the participants were asked to come to the lab and perform the same exercise moves.
‘250 mg may represent the minimum dose necessary to see performance changes’
No differences were noted between the groups for most of the exercise procedures, but the researchers observed improvement in maximum velocity and maximum mechanical power on the countermovement jump exercise.
“The data from the present study suggests that 250 mg may represent the minimum dose necessary to see performance changes,” according to the report.
Analyzing choline as a sports nutrition supplement came from the hypothesis that choline depletion is thought to play a possible role in fatigue. While studies on other forms of choline, such as choline salts or choline citrate, have had mixed results, recent studies on A-GPC have been more promising, the researchers argued.
“Future research on A-GPC should focus on larger doses for significant performance benefits, while doses lower than this should focus perhaps on other neurological benefits,” the researchers concluded.
Source: Journal of the International Society of Sports Nutrition
Published online 5 Oct 2017, https://doi.org/10.1186/s12970-017-0196-5
“Evaluation of the effects of two doses of alpha glycerylphosphorylcholine on physical and psychomotor performance”
Authors: L. Marcus, J. Soileau, L. Judge, D. Bellar