Physical activity is widely recognized as a key factor in reducing colorectal cancer risk. But did you know that exercising during the day can enhance this protective effect? A study published in BMC Medicine found that certain activity patterns, including exercising early and late in the day, were associated with a significantly lower risk of colon cancer.1
Researchers analyzed data from 86,252 participants who wore wrist-based accelerometers for seven days. The device captures 24-hour continuous physical activity data, providing a clear picture of your daily movement patterns.
Using a sophisticated method called functional principal component analysis (fPCA), the team identified four distinct activity patterns: activity during the day, late-day activity, early-day and late-day activity, and mid-day and night-time activity. Of these, early and late activity was associated with the greatest reduction in colorectal cancer risk, beyond the benefit of total activity.2
In fact, participants who followed activity patterns in the early and late mornings, such as 8 a.m. and 6 p.m. in the evening, had an 11 percent lower risk of developing colon cancer compared to participants who were less active during these hours. This two-peak pattern of activity in the morning and evening appears to offer unique benefits for prevention.
How Early and Late Exercise Supports Your Health
Why is the two-peak activity pattern so effective? The answer lies in how exercise interacts with the body’s natural rhythms. Physical activity improves metabolism, regulates insulin levels, and reduces chronic inflammation. All of these factors influence the development of cancer. Timing is important because the body’s metabolic and hormonal processes follow circadian rhythms.
For example, studies have shown that activity later in the day optimizes blood sugar levels and improves insulin sensitivity, while activity in the early hours can accelerate metabolic processes.3 Together, this combination can amplify the protective effects of exercise. Additionally, spreading out your activities throughout the day may help you avoid prolonged periods of inactivity, which has been linked to increased cancer risk.
Interestingly, this period can also affect biomarkers such as cholesterol and triglycerides. The study found that activity during the day and early morning and late morning activity patterns were weakly but positively associated with a favorable cholesterol profile and lower levels of harmful triglycerides, adding another benefit.
The role of inflammation in circadian movement patterns
The body’s circadian rhythm not only governs sleep, but also plays a role in regulating inflammation. A separate study published in Preventive Medicine found that aligning physical activity with the body’s natural rhythm amplifies the anti-inflammatory effects of exercise, significantly reducing cancer risk.4
Inflammatory markers decreased in participants who followed a circadian-friendly exercise pattern. Notably, these biomarkers were reduced due to a dual peak pattern indicating activity in both the morning and afternoon. This pattern was associated with a 29% reduction in colorectal cancer risk.5
Low levels of inflammation mediated much of the protective effect seen in reducing cancer incidence. Chronic inflammation acts as a silent driver of cancer progression, promoting processes such as DNA damage and abnormal cell growth. By spreading out activity throughout the day, it strengthens the control of the body’s inflammatory response and calms the body, which can cause hyperactivity.
A single peak pattern characterized by concentrated activity over a period of time also showed a protective effect.6 However, the advantage is less pronounced compared to the double peak pattern, highlighting the importance of timing and distribution of movement.
Morning exercise and its role in preventing breast cancer
A study published in the International Journal of Cancer also found that exercising in tune with the body’s natural rhythms offers unique cancer prevention benefits. But in this case, morning exercise was more prominent.7
Researchers examined the impact of timing of exercise on breast and prostate cancer risk and found that physical activity performed early in the morning (8 to 10 a.m.) provided the strongest protection against both cancers.
Participants who exercised during this period experienced an approximately 26% reduction in cancer risk compared to inactive individuals. Why is morning exercise so effective? Researchers have suggested that early morning exercise may help reduce breast cancer risk by influencing estrogen levels, which are closely linked to breast cancer.8
Estrogen production, especially estradiol, naturally peaks around 7 AM. Physical activity is known to lower estrogen levels, and exercising in the morning may help reduce these levels, right after the daily peak when estrogen levels are highest. This period may be particularly beneficial for hormone-sensitive breast cancers driven by estrogen.
For individuals with an intermediate or evening chronotype, who naturally prefer to wake up late or be active later in the day, morning exercise still showed a protective effect. Even moderate morning activity, such as walking or swimming, can be a powerful tool in reducing cancer risk.
Evening Exercise and Prostate Cancer — A Special Case Study
In the International Journal of Cancer study, early morning activity stood out, but evening exercise (7 p.m. to 11 p.m.) had a unique benefit on prostate cancer risk.9 Studies have shown that men who exercise in the evening have a roughly 25% reduced risk of prostate cancer compared to men who are inactive.
The protective effect of evening activity is likely related to its effect on melatonin production, which is involved in regulating processes that prevent tumor growth. Evening exercise delays the melatonin decline phase, increasing the total amount of melatonin produced during the night. This mechanism helps explain why evening activity appears to offer a unique benefit on prostate cancer risk in men.
However, evening exercise may reduce sleep quality in some people and requires careful consideration. Always listen to your body and exercise when you feel best during the day. Incorporating regular daily activities throughout the day is also key to optimal health.
Exercise also helps prevent high blood pressure.
A morning exercise routine may do more than just lower your cancer risk and energize you for the day, it may even prevent you from developing high blood pressure. A study using the UK Biobank database found that early morning exercise significantly reduced the risk of developing high blood pressure.10
The findings come from tracking 70,617 people for more than seven years, making it one of the most comprehensive studies of exercise timing and blood pressure. When researchers divided participants into groups based on exercise time, they found two particularly informative patterns.
People who exercised early in the morning had a 13% lower risk of developing high blood pressure compared to people who exercised all day, and people who exercised both early and late in the morning had a 10.5% lower risk of developing high blood pressure.
Studies have shown that just being active in the morning, even at low intensity, significantly reduces the risk of developing high blood pressure. This means that taking a morning walk or doing some light stretching is likely to help manage your blood pressure.
Synchronizing Your Exercise Timing with Your Chronotype
Interestingly, whether you’re a morning person or an evening person, your chronotype plays a pivotal role in determining the best time to exercise. For morning types, nighttime exercise increases cardiovascular risk due to a mismatch in natural rhythms. Conversely, evening types are at increased risk due to early morning activities.11
A study published in Chronobiology International found that for most people, exercising at your chronotype’s optimal time, such as noon, better aligns with your body’s natural physiology and reduces cardiovascular strain.
Midday activity, which often coincides with traditional work hours, showed the most consistent cardiovascular benefits. Short activity breaks during the day, such as walking or stretching, are very effective. If your schedule allows, aim to match peak activity times with your body’s natural rhythm to maximize benefits and minimize risks.
Additionally, if you spend most of your day sitting, it may be especially beneficial to incorporate plenty of activity into your morning and evening routine. A BMC Medicine study found that a pattern of activity throughout the day was most protective for participants with high levels of sedentary behavior.12
The findings are consistent with previous research showing that while sitting for long periods of time contributes to metabolic disorders, regular movement (even at light intensity) helps offset these negative effects.
Regular movement is key to optimal health
The body grows through consistent movement, and each type of physical activity offers unique benefits. Although the timing of exercise enhances these benefits, the basic principles remain simple. Regular exercise forms the cornerstone of good health. Establishing a consistent pattern of physical activity through daily walking, strength training, and recreational activities lays a strong foundation for overall well-being.
It is important to find personal balance. A sedentary lifestyle certainly poses health risks, but pushing yourself too hard with vigorous exercise can be counterproductive. When developing an activity routine that fits your natural rhythm and lifestyle, always listen to your body’s signals and remember that every movement counts.
Even simple activities like gardening or housework can make meaningful contributions to your daily exercise goal. Rather than focusing on one intense exercise session each day and sitting the rest of the time, aim to incorporate different forms of movement throughout the day. This balanced approach not only supports your health but also makes being active more natural and sustainable.
