Task: Question Answering
Input (English): Context: Nicotinamide adenine dinucleotide (NAD(+)) and its phosphorylated form (NADP(+)) are key molecules in ubiquitous bioenergetic and cellular signaling pathways, regulating cellular metabolism and homeostasis. Thus, supplementation with NAD(+) and NADP(+) precursors emerged as a promising strategy to gain many and multifaceted health benefits. In this proof-of-concept study, we sought to investigate whether chronic nicotinamide riboside administration (an NAD(+) precursor) affects exercise performance.', 'Eighteen Wistar rats were equally divided in two groups that received either saline vehicle or nicotinamide riboside at a dose of 300\xa0mg/kg body weight/day for 21\xa0days via gavage. At the end of the 21-day administration protocol, both groups performed an incremental swimming performance test.', 'The nicotinamide riboside group showed a tendency towards worse physical performance by 35\xa0% compared to the control group at the final 10\xa0% load (94\u2009±\u200953\xa0s for the nicotinamide riboside group and 145\u2009±\u200959\xa0s for the control group; P\u2009=\u20090.071).\Question: Does the NAD ( + ) precursor nicotinamide riboside decrease exercise performance in rats?
Output (English): Our results do not confirm the previously reported ergogenic effect of nicotinamide riboside. The potentially negative effect of nicotinamide riboside administration on physical performance may be attributed to the pleiotropic metabolic and redox properties of NAD(+) and NADP(+).