Sex Difference In The Efficacy Of High-intensity Interval Training On The Function Of Attentional Networks In Healthy Adults

Attention, a fundamental component of cognitive functions, consisted of three networks: alerting, orienting, and executive control networks. High-intensity interval training (HIIT) is a time-efficient exercise mode and has been shown to enhance brain-derived neurotrophic factor and improve neuroplasticity. Some studies have shown that sex-specific difference such as sex hormones, inflammatory and immune responses to exercise, cognitive strategies and processing play a crucial role in modulating the effects of exercise on brain functions. PURPOSE: This study aimed to explore the sex difference in the acute effect of HIIT and moderate-intensity continuous training (MICT) on the function of attentional networks in healthy adults. METHODS: Twenty women (age: 23 ± 3 years) and fourteen men (age: 24 ± 3 years) received the HIIT, MICT and the rest (CON) sessions in random order. The interval between two sessions was one week. Individual peak power output (PPO) was determined using maximal incremental cycling exercise to design the exercise regimen. The HIIT session involved alternating between one minute of cycling at 100% PPO and one minute at 20% PPO, for a total duration of 20 minutes. The MICT session involved a 30-minute cycling at 40% PPO. Each session included a 2-minute warm up and cool down at 20% PPO. The CON session had a 24 or 34-minute rest on the cycle ergometer. After each session, the function of attentional networks was evaluated using the Attention Network Test for Interactions. RESULTS: For men, although the alerting and orienting network functions did not improve in HIIT and MICT sessions relative to CON (all values of P > 0.05), executive control network function was significantly enhanced following HIIT as opposed to MICT (P = 0.026, Cohen’s d = 0.58) and CON (P < 0.001, Cohen’s d = 1.22). In contrast, for women, neither orienting nor executive network functions showed improvement in HIIT and MICT sessions compared to CON (all values of P > 0.05), while the alerting network function demonstrated a decrement following HIIT compared to CON (P = 0.024, Cohen’s d = 0.59). CONCLUSIONS: We concluded that acute HIIT enhanced the function of executive control network in men and diminished the function of alerting network in women, while having no modulation on the function of orienting network in both genders. Supported by: This research was funded by the Fundamental Research Funds for the Central Universities (the Laboratory of Exercises Rehabilitation Science)