Outdoor exercise is great, but it’s inevitably limited by the environment and weather. Having a treadmill at home changes that—you can work out whenever you want, without worrying about wind or rain. Even with a busy schedule, you can squeeze in exercise, which is truly beneficial and hassle-free for increasingly homebound urban professionals. However, some netizens have found that certain well-known treadmills are specifically labeled as “knee-friendly.” This raises the question: is running on a treadmill bad for your knees? A reporter interviewed Professor Yan Tiebin, head of the Rehabilitation Department at Sun Yat-sen Memorial Hospital of Sun Yat-sen University, who stated that while treadmill running is convenient, it’s important to be aware of contraindications and precautions—otherwise, injuries can easily occur.
Four types of people unsuitable for treadmill workouts
Many people believe that exercising is better than not exercising at all, but when it comes to choosing a workout method, most people go by preference rather than considering whether it’s “suitable,” which often leads to sports injuries. The same applies to treadmill workouts.
Professor Yan Tiebin said that running on a treadmill is different from normal running: when running normally, you can control your speed and pace, starting and stopping as you wish, and it’s less strenuous; whereas on a treadmill, the speed is usually set relatively fast with a fixed rhythm, and as long as the treadmill is running, you have to keep up with the pace continuously. Stopping suddenly can lead to falls and is also bad for the heart. Additionally, the treadmill belt keeps moving backward, requiring intense focus to avoid distraction, and the body remains much more tense than during normal running.
Given these characteristics of treadmills, experts believe that four types of people should avoid treadmill workouts—
1. People with arthritis, meniscus or ligament injuries, or those who have undergone joint replacement, as high-frequency running can cause repeated wear on the hip, knee, and ankle joints, exacerbating existing joint problems;
2. Patients with heart disease, because treadmill speed is hard to control and puts significant strain on the heart, making accidents very dangerous;
3. People with cervical or lumbar spine issues, as prolonged running in a state of high concentration can tense the neck and back muscles, and the treadmill’s recoil force may also worsen existing conditions;
4. People with osteoporosis, whose reduced bone density and loose ligaments make them prone to sprains or falls during high-intensity running, potentially leading to fractures.
Precautions for treadmill workouts
What should someone who doesn’t run often pay attention to before starting treadmill workouts? Professor Yan Tiebin said that first, it’s important to understand your physical condition—get a health check to see if you have issues like high blood pressure or diabetes, to prevent sudden blood pressure fluctuations or low blood sugar during exercise, which could be life-threatening. Additionally, it’s recommended to undergo a fitness assessment to understand your exercise limits and avoid blind or excessive training.
If you can’t find time for a check-up, you can adopt a gradual approach to running. For example, start with 5–10 minutes of slow jogging. If you feel slightly sweaty, breathe faster but not breathless, can talk without effort, and your heart rate increases by 10–20 beats compared to resting, then the intensity is appropriate. But if you’re drenched in sweat, gasping for air, and unable to speak, you should adjust the workout duration and intensity. As your endurance improves, you can gradually increase the intensity.
Professor Yan Tiebin said that proper warm-up and cool-down are needed before and after running, but he doesn’t recommend replacing them with slow jogging or walking. “Because warm-up and cool-down should involve full-body movement, like doing radio calisthenics, engaging all joints and muscles from head to toe. Just slow jogging or walking won’t achieve the goal.” He noted that generally, 5 minutes each of warm-up and cool-down are needed, along with 30 minutes of running, to have an effective workout—totaling 40 minutes per session, with sessions every other day.