Dietary Caffeine and Polyphenol Supplementation Enhances Overall Metabolic Rate and Lipid Oxidation at Rest and After a Bout of Sprint Interval Exercise
Abstract Jo, E, Lewis, KL, Higuera, D, Hernandez, J, Osmond, AD, Directo, DJ, and Wong, M. Dietary caffeine and polyphenol supplementation enhances overall metabolic rate and lipid oxidation at rest and after a bout of sprint interval exercise. J Strength Cond Res 30(7) 1871 1879, 2016 The purpose of this study was to investigate the effects of a caffeine polyphenolic supplement on (a) metabolic rate and fat oxidation at rest and after a bout of sprint interval exercise (SIE) and (b) SIE performance. In a double blind, randomized, placebo controlled, crossover study and after an initial familiarization visit, 12 subjects (male: n 11; female: n 1) (body mass 76.1 2.2 kg; height 169.8 1.6 cm; body mass index 22.7 3.0 kg*m 2; body fat 21.6 2.0% underwent 2 testing sessions during which time they consumed either a caffeine polyphenol supplement or placebo. After supplementation, resting energy expenditure, heart rate (HR) and blood pressure (BP) were assessed. Subsequently, subjects performed 30 minutes of SIE while researchers collected performance data. Subjects were then tested for post SIE energy expenditure, HR, and BP. The caffeine polyphenol treatment resulted in significantly (p 0.05) greater energy expenditure +7.99% rest; +10.16% post SIE) V[Combining Dot Above]O2 +9.64% rest; +12.10% post SIE) and fat oxidation rate +10.60% rest; +9.76% post SIE) vs. placebo at rest and post SIE. No significant differences were detected for peak and average power at all sprint intervals between treatments. Post SIE HR was significantly (p 0.05) greater with caffeine polyphenol supplementation vs. placebo (90.8 3.5 vs. 85.1 3.6 b*min 1) There were no significant between treatment differences for BP. It may be concluded that the observed thermogenic response after SIE was directly attributable to caffeine polyphenol supplementation as opposed to an indirect manifestation of enhanced performance and work output. Collectively, these results corroborate the use of dietary caffeine and polyphenols to support efforts to reduce adiposity and improve overall body composition especially in conjunction with SIE.
Journal of strength and conditioning research