Avoiding daytime heat exposure, night running has become a top summer exercise choice for many. But nighttime runs come with their own considerations. Poorly planned sessions can backfire, leading to poor sleep, digestive discomfort, and overall fatigue. Let’s explore how to run scientifically at night. Timing Matters Opt for runs between 7 PM and 9 PM, when temperatures drop and lighting conditions are suitable. Avoid overdoing duration or distance—5 kilometers is sufficient for daily exercise. High-intensity workouts keep the sympathetic nervous system overactive, disrupting circadian rhythms and affecting sleep onset and quality. Expert Advice on Intensity Xie Xing, Chief Physician of Sports Medicine at Peking University Third Hospital: “Normally, I suggest adjusting intensity when your heart rate reaches twice your resting rate—approaching 180 beats per minute.” Fasted or Post-Meal Running? Liu Wei, Assistant Researcher at the same department: “Both options work for most people. Short, low-intensity runs on an empty stomach are fine. However, those prone to hypoglycemia or elderly individuals with low stamina should avoid fasting before running. For meal timing: aim for moderate-intensity exercise 1 hour after eating, and high-intensity workouts 2 hours post-meal.” 

 Excessive Sweating During Summer Exercise Scientific Replenishment of Electrolytes During summer exercise, sweating increases significantly. Heavy perspiration not only depletes water but also causes loss of essential electrolytes like sodium, potassium, and magnesium. Experts warn that hydration alone is insufficient—electrolyte imbalance can trigger various physical discomforts. After prolonged, high-intensity exercise, excessive sweating disrupts the body’s electrolyte balance, leading to symptoms such as muscle cramps, numbness in extremities, generalized fatigue, dizziness, and nausea. In severe cases, it may result in dehydration or collapse. Thus, replenishing electrolytes promptly after exercise is critical. How to Correctly Replenish Electrolytes During Exercise? Liu Wei, Assistant Researcher at the Department of Sports Medicine, Peking University Third Hospital: “For moderate-to-high intensity exercise lasting over 40 minutes (or even an hour), especially with heavy sweating, consume electrolyte drinks or sports beverages. Follow the principle of ‘small amounts, frequent intake’—for example, take 150–200 mL of electrolyte/sports drink every 15–20 minutes.” Dietary sources of electrolytes are primarily found in vegetables and fruits. Bananas, tomatoes, watermelons, and dark-colored leafy vegetables are particularly rich in electrolytes. Avoid Summer Exercise Myths: Exercise Scientifically to Protect Your Health In the scorching summer, many people persist in exercising, but some misconceptions can actually harm their health. Myth 1: The more you sweat, the better the fat-loss effect? Liu Wei, Assistant Researcher at the Department of Sports Medicine, Peking University Third Hospital: “Fat loss has no direct correlation with sweating volume—it’s more closely tied to exercise intensity and duration. To achieve effective fat loss, we recommend 150–300 minutes of moderate-intensity aerobic exercise weekly for weight control.” Myth 2: Muscles feel soft in summer, so warm-ups are unnecessary? Xie Xing, Chief Physician of Sports Medicine at Peking University Third Hospital: “Warm-ups serve two purposes: raising heart rate and activating muscles. Even in summer’s high temperatures, muscles remain stiff without stretching. Sudden intense exertion without proper warm-up can lead to muscle injuries. Thus, warm-ups are still essential in summer.” (Source: Liaowang New Era)