Evaluation of Ocular Higher-Order Aberrations in Patients with Migraine: A Comparative Study.

Meta-analyses have evidenced that exercise training can enhance various aspects of cognitive function in healthy older adults (; ; ). Studies have implicated exercise in enhancing the signaling pathways of neurotrophic factors (NTFs), which are essential for cognitive function and combating neurodegenerative diseases (; ; ). These factors, including brain-derived neurotrophic factor (BDNF) and insulin-like growth factors, are believed to mediate the protective and therapeutic effects of exercise on brain function (; ). BDNF, which is widely expressed in the human brain, plays a critical role in neuroregulation, neuroprotection, neurogenesis, and neuroplasticity (; ). However, the concentration of BDNF in the blood declines with age, and this decline is associated with cognitive decline and the progression of neurodegenerative diseases (; ; ; ; ; ). Exercise training positively impacts body composition, bone health, metabolism, and cognitive function in older adults. Studies on BDNF responses have primarily focused on aerobic exercise, with recent meta-analyses confirming that aerobic exercise increases serum or plasma BDNF levels (; ; ). However, resistance training effectively reduces the risk of sarcopenia, falls, fractures, and disability () and may also enhance cognitive function in older adults by increasing blood-borne neurotrophic factors (). Resistance training is a more complex modality than aerobic exercise, requiring careful consideration of intensity, repetitions, and rest durations. The recommended training prescription varies depending on the desired outcome, such as muscular power, strength, hypertrophy, and endurance. In particular, a highintensity, low-repetition modality is typically used for increasing muscular strength, whereas a low-intensity, high-repetition modality is more suitable for increasing muscular endurance. Small adjustments in the training prescription can significantly influence outcomes due to the cumulative effects of different training modalities. Studies on resistance training and BDNF have often employed single-set interventions and may have varied in their training goals, leading to inconsistent results. categorized resistance training into high resistance (2 sets × 10–15 repetitions × 80% 1 repetition maximum (RM)), low resistance (1 set × 80–100 repetitions × 20% 1 RM), and mixed low resistance (1 set × 60 repetitions × 20% 1 RM + 1 set × 10–20 repetitions × 40% 1 RM). They reported that only the mixed low-resistance long-term training modality significantly increased BDNF levels in older adults. However, the unconventional nature of this prescription made it difficult to determine why it yielded more favorable results. employed a more conventional strength training prescription and reported that both muscular endurance and muscular strength-oriented resistance training modalities increased BDNF levels in young adults. By contrast, reported that only hypertrophy training was effective in increasing BDNF levels. Although the effectiveness of high-intensity modalities remains debated, their importance in delaying disability in older adults should not be overlooked. Further research is warranted to clarify the potential benefits of high-intensity resistance training on BDNF levels.