Singer Reina shows off bikini figure — does night running actually help you lose weight?

Singer Reina's vacation photos in a bikini have drawn fresh attention to her exercise habits. She had previously shared footage of herself on a late-night run along the Han River, and experts say light evening running can aid weight management, blood sugar control and stress relief. They caution, however, that high-intensity workouts right before bed can disrupt sleep, making it important to adjust both the intensity and timing of exercise.

Reina recently posted several photos on her SNS showing her enjoying a poolside vacation. In the images, she posed in a bikini, drawing attention for her trim waistline.

Maintaining a lean physique requires not only a controlled diet but also a consistent exercise routine. Running in particular is a representative aerobic workout that requires no special equipment — it engages large muscle groups throughout the body, boosting energy expenditure and building cardiovascular endurance.

Evening or nighttime running can help make up for a lack of physical activity during the day. For people who sit at a desk all day or move very little, even a light walk or jog after work can meaningfully increase total energy expenditure. Ultimately, the key to weight loss is consistently burning more calories than you consume.

Light exercise after dinner can also help with blood sugar management. Blood sugar rises after meals, but low-intensity aerobic activity such as walking or a gentle jog prompts muscles to use glucose as fuel, helping to blunt the post-meal spike. That said, running hard immediately after eating can cause stomach discomfort or digestive strain, so it is best to wait about 30 minutes to an hour after a meal before starting.

Night running can also relieve stress. As your heart rate rises and your body warms up, tension tends to ease. The gradual drop in body temperature after exercise can sometimes help prepare the body for sleep — though this applies only when the workout is not too intense.

High-intensity running right before bed, however, can have the opposite effect and interfere with sleep. Vigorous exercise activates the sympathetic nervous system and raises both heart rate and body temperature, making it harder to fall asleep. For a good night's rest, finish exercise at least one to two hours before bedtime and wind down afterward with light stretching and a shower.

Safety is the most important consideration when running at night. Visibility is reduced after dark, and vehicles, cyclists and pedestrians may not notice one another until it is too late. Avoid isolated roads and dark alleys, and stick to familiar, well-lit routes such as park paths, the Han River walkway or a running track.

What you wear matters too. Bright-colored or reflective running gear is far safer than dark clothing. Keep your phone adequately charged, and if you use earphones, keep the volume low enough to hear your surroundings.

Exercise intensity should match your fitness level. Rather than pushing for a long run from the outset, alternating between brisk walking and slow jogging puts less strain on the body. If you are too breathless to hold a conversation, the intensity is too high — beginners or those returning to exercise after a long break should be careful not to overdo it.

Running alone will not sculpt your physique. Strength training is also needed to define the waistline and build a toned body. While running can help reduce body fat, insufficient muscle mass means the body may look soft even after losing weight. Doing basic strength exercises — squats, lunges, planks and hip bridges — two to three times a week helps maintain lower-body and core muscle.

Diet must go hand in hand with exercise. Eating high-calorie late-night snacks after a workout because you feel hungry can easily cancel out the calories burned. After an evening run, opt for lighter options — water, unsweetened yogurt, boiled eggs, tofu or a banana — rather than ramyun, fried chicken or other heavy late-night fare.

Experts advise against treating night running as a special weight-loss secret, and instead recommend making it a sustainable lifestyle habit. The point, they say, is not that running at night burns fat faster than running during the day — it is that exercising regularly at whatever time you can stick to matters most for weight management and overall health.