A Close Look at NO2
"Effects of Arginine-Alpha-Ketoglutarate Supplementation on Body Composition and Training Adaptations" was presented by Bill Campbell, et al.
Arginine-alpha-ketoglutarate (AKG) has recently grown in popularity in the dietary supplement world. It is more commonly known as NO2 and is purported to increase nitric oxide synthesis, thereby enhancing blood flow, oxygen delivery, and glucose uptake. All could lead to enhanced muscle mass and strength during training. While sales have recently surged, it has not really undergone scientific scrutiny-until now.
The purpose of this study was to examine how an AKG supplement would affect muscle strength and overall muscle mass during training. Thirty-five resistance-trained males were matched for fat free mass and assigned to either take an NO2 supplement or a placebo. Subjects ingested 12 grams of the product per day for eight weeks during standardized training.
At 0, 4, and 8 weeks, body composition was measured and subjects performed one repetition maximum (RM) bench press, an isokinetic endurance test, a cycling anaerobic capacity test, and a max cardiopulmonary exercise test on a treadmill.
There were no significant differences between groups in body mass, fat free mass, or percent body fat. There were also no significant differences in average power or total work. On the other hand, changes in 1 RM bench press, sprint peak power, time to peak power, and rate to fatigue were all significantly greater in those taking the NO2 supplement than in those taking the placebo. However, no mechanism was suggested and this is the only study on NO2 to date.