Morning Exercise Shows Promising Effects in Preventing Chronic Diseases

Source: Life Times

Expert Interviewees: Ren Jingjing, Chief Physician, Department of General Practice, the First Affiliated Hospital of Zhejiang University School of Medicine; Cui Xiaorong, Associate Chief Physician, Department of Geriatrics and Special Care Medicine, Southwest Hospital of Army Medical University

"The plan for the day lies in the morning" — a phrase deeply rooted in Chinese people's collective growth memory — still holds true today, especially in the field of physical activity. A latest study published in Journal of the American College of Cardiology on March 27 found that people who habitually exercise in the morning have significantly lower risks of coronary heart disease, hypertension, diabetes and obesity compared to those who work out later in the day. In particular, the period from 7 a.m. to 8 a.m. is regarded as the golden window for morning exercise.

"When you exercise" matters as much as "how long you exercise"

This new study analyzed long-term health records of more than 14,000 participants. Instead of focusing on specific sports events, it linked physical activity to elevated heart rate as a core judgment indicator. Any activity that effectively stimulates cardiopulmonary function — including walking for commuting, doing housework, or working out in the gym — was counted as valid exercise. Researchers assessed participants' movement patterns every 15 minutes throughout the day.

The analysis results showed that compared with people who exercised later, morning exercisers had their risks of coronary artery disease, hypertension, hyperlipidemia, type 2 diabetes and obesity reduced by 31%, 18%, 21%, 30% and 35% respectively. Among all time windows, exercising between 7 a.m. and 8 a.m. brought the lowest risk of coronary artery disease. Furthermore, among populations with similar total daily activity volume, those who moved earlier in the day presented better cardiometabolic indicators.

The World Health Organization recommends that adults accumulate at least 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous-intensity activity per week, with duration and intensity as the two traditional criteria for health benefits. Cui Xiaorong, Associate Chief Physician of the Department of Geriatrics and Special Care Medicine at Southwest Hospital, Army Medical University, told Life Times that in most cases, the public and even some medical practitioners focus too much on meeting the "150-minute weekly target" and exercise intensity, while ignoring the critical variable of exercise timing.

Ren Jingjing, Chief Physician of the Department of General Practice at the First Affiliated Hospital of Zhejiang University School of Medicine, added that the timing and duration of exercise affect health through different dimensions, and both are equally important. "Exercise duration determines the total daily activity volume. Only when the total volume reaches the standard can we gradually accumulate health benefits such as maintaining cardiopulmonary function and enhancing metabolism. Exercise timing, on the other hand, acts as an 'amplifier' for health gains — on the premise of the same amount of exercise, choosing the right time can maximize the overall effect."

Why chronic disease prevention benefits most from morning activity

The effectiveness of morning exercise in preventing chronic diseases does not come from simple physical movement alone, but relies on a complete and rigorous self-regulation mechanism in the human body.

It aligns with the power of the circadian rhythm. Ren Jingjing explained that the human circadian clock is a precise system that strictly follows the day-night cycle, with hormone secretion, body temperature changes, glucose and lipid metabolism all showing a pattern of "higher in the daytime and lower at night". Early morning is exactly the critical transition period when the body shifts from resting state to active state. Exercising at this time conforms to the natural law of "working at sunrise", which can activate the activity of metabolism-related enzymes, improve insulin sensitivity, and achieve twice the result with half the effort in lowering blood glucose, reducing blood lipids and managing weight — all of which are key to the prevention and control of "three highs" (hypertension, hyperglycemia, hyperlipidemia) and cardiovascular and cerebrovascular diseases.

It supports synergistic effects between exercise and medication. Early morning is a "warning period" when blood pressure naturally rises and cardiovascular events occur more frequently. According to Cui Xiaorong, this is a natural physiological instinct of the human body, but moderate morning exercise can help blood vessels gradually adapt to this change, while improving vascular endothelial function and enhancing the body's own blood pressure regulation ability. For people taking antihypertensive or hypoglycemic drugs, morning exercise can form a "synergistic effect" with medications, making blood pressure and blood glucose indicators more stable throughout the day — on the premise that morning exercise is carried out at least one hour after taking the medicine.

It improves mood and energy levels. Cui Xiaorong pointed out that morning exercise not only wakes up the body, but also stimulates the brain to secrete large amounts of "happy hormones" such as endorphins and dopamine, which helps relieve negative emotions like anxiety, improve daytime concentration, and enhance deep sleep at night, forming a positive cycle of "exercise — better state — better sleep". This benefit is especially prominent for people aged 60 and above. A latest study published in Chronobiology International on March 26 found that early morning is the period when this group has the highest sense of inner well-being and the most abundant energy. This positive state makes it more likely for people to make healthier choices throughout the day, such as eating nutritious food and avoiding late-night snacking.

Another major advantage of morning exercise is that it is easier to form a long-term habit, as it is usually completed before going to work, attending classes or taking on family responsibilities. In contrast, plans to exercise at noon or in the evening are more likely to be disrupted by unexpected events such as work tasks and social arrangements.

Safety is the top priority

Although morning exercise brings many benefits, it is not suitable for everyone. Ren Jingjing reminded that the elderly, people with diabetes and those prone to low blood sugar are at higher risk of dizziness, palpitation, fatigue and even syncope when exercising in the early morning, especially on an empty stomach. Therefore, morning exercise for different populations should make individualized adjustments on the basis of following general safety principles.

For adults, the core is consistency. It is recommended to prioritize 30 to 40 minutes of moderate-intensity exercise between 7 a.m. and 8 a.m., such as brisk walking and jogging. The target heart rate should reach 50% to 70% of (220 minus your age), which can activate metabolism, reduce fat, and avoid excessive physical exhaustion. Simple strength training with body weight, such as planks, push-ups, squats and wall sits, can also be included to stimulate muscles and improve physical strength.Important reminders: Do not exercise immediately after waking up. Drink 100 to 200 milliliters of warm water first, then do 10 minutes of full warm-up. Avoid long-duration, high-intensity exercise on an empty stomach. If you have a tight schedule in the morning, 15 to 20 minutes of brisk walking is also effective. You do not have to force yourself to "complete 30 minutes" — persistence is more important than duration.

For the elderly, the core principle is "stability". The goal of morning exercise for seniors is to maintain muscle strength, balance ability and cardiopulmonary function, reduce the risk of falls and cardiovascular events, rather than pursuing high intensity. It is recommended to avoid unfavorable weather conditions such as low temperature, cold wave and strong wind, and choose the period after sunrise with suitable temperature (8 a.m. to 9 a.m.) to do about 30 minutes of low-to-moderate intensity exercise, with appropriate balance training added. Suitable options include Tai Chi, Baduanjin and square dance. On rainy or hazy days, it is better not to go outdoors, and simple stretching or marching in place can be done indoors.

Important reminders: The elderly must never exercise on an empty stomach. Eat a small amount of easily digestible food before morning exercise, and extend the warm-up period to 15 to 20 minutes. Avoid sudden force or breath-holding during exercise. It is best to exercise with companions, and carry first-aid medicines (such as nitroglycerin) with you. If you feel unwell such as dizziness, palpitation or chest tightness, stop exercising immediately and seek medical attention in time when necessary.

For people with chronic diseases, "safety first" must always be kept in mind. Patients with hypertension should avoid the early morning blood pressure peak period (6 a.m. to 8 a.m.), and prioritize gentle aerobic exercises such as Tai Chi and slow walking. They must measure blood pressure before exercising, and never work out if the blood pressure exceeds 160/100 mmHg. Patients with diabetes must have breakfast first, which should be "low-sugar, high-fiber and easy to digest", such as multigrain porridge with eggs. They can carry out moderate-intensity exercise 0.5 to 1 hour after the meal, and carry emergency foods such as candies and biscuits with them to watch out for hypoglycemia symptoms like palpitation, hand tremor and sweating. They must not exercise if blood glucose is lower than 4.4 mmol/L or higher than 16.7 mmol/L. Patients with knee joint diseases should avoid movements such as squats, jumping and stair climbing, and swimming and walking are more recommended. A single exercise session should not exceed 30 minutes, and they must not exercise during the inflammatory period with redness, swelling, heat and pain.

Cui Xiaorong emphasized that the new study only reveals the correlation between morning exercise and reduced chronic disease risk, rather than a direct causal relationship. There is no need to deny the value of exercising at noon or in the evening — any time of physical activity is better than no exercise. For example, a study from Maastricht University in the Netherlands found that if the goal is to lower blood glucose, the afternoon (12 p.m. to 6 p.m.) is the "golden period" for exercise: adding 10 minutes of light activity can reduce the risk of type 2 diabetes by 18%. Moderate to high-intensity exercise in the evening (6 p.m. to 12 a.m.) also brings prominent benefits, but late-night exercise (12 a.m. to 6 a.m.) is an absolute "red line" — even a small amount of activity such as walking may cause serious negative impacts on metabolism.

Finally, it should be reminded that appropriate amount of sweating during exercise, slight sense of fatigue, physical and mental comfort after activity, heart rate returning to normal within about 10 minutes, good sleep and appetite, and full energy the next day are all signals of proper exercise volume. Conditions such as excessive sweating or no sweating at all, extreme fatigue or no sense of fatigue, poor sleep and appetite, heart rate failing to recover within 15 minutes, or recovering in less than 3 minutes, all indicate inappropriate exercise intensity.

Disclaimer: The information in this article is for popular science reference only, and does not constitute medical diagnosis advice.