Exercising before a nap benefits memory better than napping or exercising alone.

Sleep. 2020 Apr 01;:

Authors: Mograss M, Crosetta M, Abi-Jaoude J, Frolova E, Robertson E, Pepin V, Dang-Vu TT

Abstract

Sleep leads to the enhancement of memory, and physical exercise also improves memory along with beneficial effects on sleep quality. Potentially, sleep and exercise may operate independently upon memory; alternatively, they may operate synergistically to boost memory above and beyond exercise or sleep alone. We tested this hypothesis in 115 young healthy adults (23±3.9 years) randomly allocated to one of the four conditions in a 2 (exercise vs no exercise) x 2 (nap vs no nap) design. The exercise intervention consisted of a 40-min, moderate-intensity cycling, while the no exercise condition was an equivalent period of rest. This was followed by a learning session in which participants memorized a set of 45 neutral pictures for a later test. Subsequently, participants were exposed to either a 60-min sleep period (nap) or an equivalent time of resting wakefulness, followed by a visual recognition test. We found a significant interaction between the effects of exercise and nap (p=0.014, ?p2 = 0.053), without significant main effects of exercise or nap conditions. Participants who experienced both exercise plus nap were significantly more accurate (83.8±2.9) than those who only napped (81.1±5.4, p=0.027) and those who only exercised (78.6±10.3, p=0.012). Within the combined nap plus exercise group, higher recognition accuracies were associated with higher sleep spindle densities (r = 0.46, p=0.015). Our results demonstrate that short-term exercise and a nap improve recognition memory over a nap or exercise alone. Exercise and sleep are not independent factors operating separately upon memory but work together to enhance long-term memory.

PMID: 32236442 [PubMed - as supplied by publisher]