A new wave of international research is reshaping what we know about the best—and worst—times to exercise for a better night’s sleep, with insights directly relevant to Thai health enthusiasts, students, and working professionals navigating busy urban lives. While the long-held belief warned against late-night workouts, new expert consensus suggests that timing, exercise type, and individual “chronotypes” all affect how our bodies wind down for rest and recover throughout the night.
Recent studies highlighted in a widely read Real Simple article reveal how regular exercise aids sleep by harmonizing the circadian rhythm—our internal body clock that follows the natural day-night cycle. According to a sleep science advisor cited in the article, movement triggers endorphin release, reduces stress, and boosts serotonin, a precursor to melatonin, the hormone essential for sleep regulation. Moreover, the rise in core body temperature during exercise is later followed by cooling, sending signals to the brain that it’s time to rest. This physiological process aligns with foundational recommendations in sleep hygiene, which have long encouraged people to avoid strenuous physical activity right before going to bed (“Sleep hygiene,” Wikipedia).
Leading international sleep experts, such as those from the National Sleep Center and the Yale School of Medicine, converge on the idea that morning exercise provides the strongest support for restful sleep, especially for early risers. As explained by a director at the National Sleep Center, exposure to morning light during exercise helps establish a robust circadian rhythm. Not only does this energy boost promote productivity during the day—a claim echoed by fitness advisors in Thailand (“Should I Run in the Morning?”, ASICS)—but it also primes the body to start producing melatonin as light fades in the evening, naturally cueing sleepiness at bedtime.
A 2025 cross-sectional study from the Dutch population published on PubMed further reinforces this: those who exercised earlier in the day (morning or early afternoon) reported higher sleep quality and longer sleep durations compared to those who exercised late in the evening. The researchers underscored that moderate-to-vigorous activity showers the body with sleep-supporting hormones and engages muscles in ways that encourage restorative rest later in the night (Amount and timing of physical activity in relation to sleep quality, PubMed).
But what about the increasing number of Thais who can only fit workouts in after dark due to social or work obligations? The evolving research does not categorically ban evening exercise, but emphasizes caution around intensity and timing. A recent Nature Communications study found a clear “dose-response” relationship: strenuous evening workouts, especially less than four hours before bedtime, disrupt not only how fast we fall asleep, but also the quality and quantity of sleep itself. Elevated core body temperature, heightened adrenaline, and increased sympathetic nervous system activity can keep the mind and body in “go” mode longer than desired (Dose-response relationship between evening exercise and sleep, Nature). A similar 2025 study led by Monash University demonstrated that high-intensity exercise late at night triggers physiological changes akin to pre-competition arousal, reducing both sleep duration and depth (“Exercise before bed is linked with disrupted sleep,” Medical Xpress).
However, light activities such as yoga or gentle resistance training may actually benefit sleep when done in the evening—so long as the session ends at least two hours prior to bedtime, according to sleep specialists from Yale. Yoga, in particular, engages the parasympathetic nervous system and is praised for reducing stress, calming the mind, and preparing the body for restful sleep, making it a promising option for urban Thais often juggling high stress and late working hours.
Another crucial finding in the literature is the role of individual chronotype—whether one naturally wakes early (“early bird”) or prefers late nights (“night owl”). Experts point out that early risers benefit most from exercising in the morning or early afternoon when their circadian rhythm is primed for activity. Night owls, though more comfortable exercising later, should still aim to complete strenuous workouts at least 90 minutes before sleep to mitigate disruption.
Practical implications for Thai society are significant. Many Thais, particularly in Bangkok and other big cities, face long commutes and evening obligations, making late-night gym visits and group fitness classes ever more popular. Thai public health officials have also advocated exercise as a stress-reduction method, especially as the country grapples with rising rates of sleep disorders and chronic non-communicable diseases (“Is It Better To Work Out in the Morning or the Evening?”, GQ). Yet, as new science emerges, there’s a need for nuanced health messaging: while any regular exercise is better than none, both timing and intensity matter for optimal sleep and overall wellbeing.
Cultural context is also noteworthy: many traditional Thai exercise groups, especially among older adults, meet during the early morning for communal aerobics, tai chi, or walking in public parks. This practice may unwittingly align with the latest global research, explaining, in part, the high level of sleep satisfaction often self-reported among these groups. Conversely, urban youth and working adults flock to nighttime Muay Thai or HIIT classes, sometimes finishing close to midnight. As seen in the new studies, this could be inadvertently sabotaging sleep quality and next-day performance, despite boosting stress relief in the moment (“Is it okay to workout at night? Pros & Cons of P.M exercises”, Watsons Thailand).
Looking ahead, ongoing research is exploring individualized exercise prescriptions that account for personal chronotype, lifestyle constraints, and genetic predisposition (“The relationship between physical activity level and timing and sleep quality,” BMC Public Health). Experts urge everyone to prioritize consistency over perfection: regular movement at any time of day improves sleep and health over a sedentary lifestyle. However, aiming for earlier workout times—notably in the morning or early afternoon—may deliver the best results, especially for those struggling with insomnia, jet lag, or irregular sleep schedules (“The impact of exercise on sleep and sleep disorders”, Nature).
For Thais seeking the “sweet spot,” health professionals recommend these practical steps: try morning or lunchtime workouts if your schedule allows; combine aerobic exercise, resistance training, and calming activities like yoga throughout the week; avoid vigorous activity within at least two hours of sleeping, opting for gentler forms if needed; and tune your routine to both your biological rhythm and professional demands. If you must exercise in the evening, finish high-intensity sessions as early as possible, and lean into slower, more restorative movement close to bedtime.
Ultimately, as a Thai sleep expert from a leading Bangkok hospital puts it, “What matters most is making exercise a regular habit, tailored to your lifestyle, and staying attentive to how your body responds. Good sleep is the foundation of physical and mental health—by timing your workouts wisely, you’re already one step ahead.” Consistency, balance, and self-awareness remain the pillars of a sleep-supportive lifestyle, even as the science evolves.
For those interested in more details—and for actionable advice tailored to specific age groups or medical histories—consult your local healthcare provider or check with the Department of Health’s public resources on sleep and wellbeing.
Sources:
- “The Best—and Worst—Times to Exercise for a Good Night’s Sleep,” Real Simple
- “Dose-response relationship between evening exercise and sleep,” Nature
- “The impact of exercise on sleep and sleep disorders,” Nature
- “Exercise before bed is linked with disrupted sleep,” Medical Xpress
- “Amount and timing of physical activity in relation to sleep quality,” PubMed
- “Sleep hygiene,” Wikipedia
- “Should I Run in the Morning?”, ASICS Thailand
- “Is it okay to workout at night? Pros & Cons of P.M exercises,” Watsons Thailand
- “The relationship between physical activity level and timing and sleep quality,” BMC Public Health