Bodybuilders have long touted the value of the “pump” for increasing muscle size. The blood accumulation in the working muscle and the accompanying swelling create the micro-tears that stimulate the need for protein synthesis and muscle repair and simultaneously deliver the nutrients needed for that growth and repair process.
Supplements that increase vasodilation, or the expanding of the blood vessels, have long been on the market, with l-arginine leading the way. The function of this amino is to increase blood nitric-oxide (NO) levels, dilating the vessels for improved oxygen delivery. Unfortunately, l-arginine taken orally has been shown to have limited if any effect on blood NO levels. It was initially used in hospitals in patients recovering from diseases that had led to muscular atrophy (shrinking) and was found effective, but only intravenously. A subsequent form, Arginine Alpha Ketogluterate (AKG) was found in tests done at the University of Florida to be superior to l-arginine in its bioavailability when taken orally, but still only marginally effective. Much of the effective “pump” perception is considered by some researchers to be merely the placebo effect.
There is another answer to the NO/vasodilation pursuit, however. Many vegetables contain nitrate (NO3) which is readily absorbed. Saliva breaks the NO3 down into nitrite, which is then swallowed and converted in the gut into biologically active molecules. In fact, during exercise, the absorption is actually ENHANCED!
All leafy green vegetables contain nitrates, but beetroot juice has one of the highest nitrate concentrations among all vegetables, making it ideal for aiding in the achievement of increased NO and vasodilation, thereby enhancing the pump. “…beetroot has been shown to mediate an array of biological responses, including that of muscle contractility, hypoxi vasodilation resulting in a reduction in blood pressure, a reduction in O2 cost during exercise, and modulation of muscular contration and glucose uptake, thus possibly optimizing perfromnace.” - NSCA Strength and Conditioning Journal, v. 34, n. 4, August 2012.