Effect Of Transcutaneous Delivery Of Sodium Bicarbonate On Intramuscular Ph.

Abstract

Oral bicarbonate loading improves the buffering of metabolic acidosis and can improve exercise performance but can also result in gastric distress. PR Lotion contains a novel composition thought to provide a transdermal delivery vehicle for sodium bicarbonate that could have the same ergogenic effect without the likelihood of gastric distress. PURPOSE: Assess the effect of the transdermal delivery vehicle of sodium bicarbonate in a resting condition. METHODS: In 9 subjects (3 women, 6 men; 30 ± 8y), we measured the pH of intramuscular dialysate using a low-volume flow-through pH microelectrode before and for 2 h after PR Lotion application (40 g per leg). Additionally, we measured serum pH collected at baseline and 30, 60, 90, and 120-min after application. A placebo time control was later performed in 4 subjects (2 women, 2 men; 28 ± 3y). The change in pH from baseline to the end-of-study was assessed via univariate t-test. In addition, a Pearson moment correlation was used to explore the relation between applied dose (g/kg body weight) and change in pH. RESULTS: Following PR Lotion application, intramuscular dialysate pH increased 0.13 ± 0.04 units (p < 0.05), which translates to a 28% reduction in [H+]. The effect on intramuscular dialysate pH tended to correlate with the applied dose in grams per kg of bodyweight (r = 0.70, p = 0.080). Changes in serum pH following PR Lotion application were smaller (~9%) yet consistent (p < 0.05). In contrast, intramuscular dialysate pH tended to decrease in the placebo time control (p = 0.08). CONCLUSION: These observations support the concept of transdermal bicarbonate delivery impacting pH buffering both intramuscularly and systemically. Further work investigating these potential benefits in an exercising model would be advantageous and critical to determining PR Lotion’s utility as an ergogenic aid.This research was funded, in part, by a research contract from Amp Human