|Pyruvate = Recomp agent, not performance enhancer?|
The idea was that pyruvic acid could supply energy to working muscles through the citric acid cycle (also known as the Krebs cycle) when oxygen is present (aerobic respiration), and alternatively ferment to produce lactate when oxygen is lacking (fermentation) - this would make it the perfect workout fuel for high intensity exercise, but theory and practice are two very different animals.
Past studies investigating its efficacy have however yielded mixed results. In the year 2000, Michael A. Morrison , Lawrence L. Spriet , David J. Dyck reported that "oral pyruvate supplementation does not increase blood pyruvate content and does not enhance performance during intense exercise in well-trained cyclists." (Dyck. 2000)
Similarly disappointing results have been reported by Ebersole et al., likewise in the year 2000 for improvements in critical power (there were none) and stand in contrast to observations by JL Ivy who found that pyruvate, when "provided as an oral supplement for several days", whill "enhance aerobic endurance capacity" in rodents (Ivy. 1998) or Stanko et al. who found back in 1990 that feeding dihydroxyacetone and pyruvate for 7 days increased arm muscle glucose extraction before and during exercise, thereby enhancing submaximal arm endurance capacity of (albeit) untrained men.
|Weight & amp;fat loss(kg)/4.25-MJ deficit (Stanko. 1995) ➽ Pyuruvate makes dieting more effective.|
"Since 0.1 g of sodium bicarbonate per kg of body mass induces metabolic alkalosis 60 min following ingestion [14,15], we hypothesized that a similar NaP treatment before commencing the high intensity physical exertion may change the exercise metabolism." (Olek. 2014)Nine active, but non-specifically trained, malesubjects (mean ± SEM: 23 ± 1 year old, 1.75 ± 0.02 m height, 72 ± 2 kg body mass) participated in the double-blind, placebo-controlled, crossover study.
"On separate days, the subjects reported to the laboratory in the morning, then rested for 30 min and then ingested placebo or NaP in a random order. In the previous studies the subjects consumed PYR in the amount of ~0.07–0.08 g/kg body mass; therefore, the subjects in our study ingested NaP in a single dose of 0.1 g/kg body mass (which is ~0.08 g of PYR per kg body mass). " (Olek. 2014)An hour following the ingestion, the subjects performed the physical exertion. The exercise protocol consisted of 2 min at a power output of 50 W and then for 6 min at a constant power output, corresponding to ~90% O2max. To determine O2max, participants performed a graded cycle ergometry test on an electromagnetically-braked, cycle ergometer. After an initial warm-up period, the work rate was increased by 25 W/min until volitional exhaustion was achieved.
|Figure 1: Lactic acid and blood pH during the placebo (•) and (o) pyruvate trial (Olek. 2014)|
Pyruvate as a PGC-alpha driven metabolic engine builder: In view of the fact that high pyruvate levels would usually occur during intense exercise it's no wonder that researchers from Novartis Institutes for BioMedical Research in Cambridge have found that it increases mitochondrial biogenesis in rodent muscle (Wilson. 2007)
And even when it was administered as creatine pyruvate, Van Schuylenbergh et al. did not find any benefits on cycling performance in a 2003 study.
- Ebersole, Kyle T., et al. "The Effect Of Pyruvate Supplementation On Critical Power." The Journal Of Strength & Conditioning Research 14.2 (2000): 132-134.
- Ivy, John L. "Effect of pyruvate and dihydroxyacetone on metabolism and aerobic endurance capacity." Medicine and science in sports and exercise 30.6 (1998): 837-843.
- Kalman, Douglas, et al. "Effect of pyruvate supplementation on body composition and mood." Current Therapeutic Research 59.11 (1998): 793-802.
- Koh-Banerjee, Pauline K., et al. "Effects of calcium pyruvate supplementation during training on body composition, exercise capacity, and metabolic responses to exercise." Nutrition 21.3 (2005): 312-319.
- Morrison, Michael A., Lawrence L. Spriet, and David J. Dyck. "Pyruvate ingestion for 7 days does not improve aerobic performance in well-trained individuals." Journal of Applied Physiology 89.2 (2000): 549-556.
- Stanko, Ronald T., Denise L. Tietze, and Judith E. Arch. "Body composition, energy utilization, and nitrogen metabolism with a 4.25-MJ/d low-energy diet supplemented with pyruvate." The American journal of clinical nutrition 56.4 (1992): 630-635.
- Van Schuylenbergh, Reinout, Marc Van Leemputte, and Peter Hespel. "Effects of oral creatine-pyruvate supplementation in cycling performance." International journal of sports medicine 24.02 (2003): 144-150.
- Wilson, Leanne, et al. "Pyruvate induces mitochondrial biogenesis by a PGC-1 α-independent mechanism." American Journal of Physiology-Cell Physiology 292.5 (2007): C1599-C1605.