If you only talk about the weight loss effect: almost the same effect. The essence of losing weight is to catabolize fat through exercise. Whether running outdoors or on an indoor treadmill, the human body continues to work and consume calories, so you can lose weight. The two running methods work differently. Although they all burn fat, there is no objection to this, but there are fundamental differences in the way of exertion. In outdoor running, the oxygen content is definitely more abundant than indoors. This slight difference will not be mentioned. The main problem is that whether you notice it or not， when you run forward outdoors, you must push your toes forward. You will move forward, this time relying on the force of the calf, which can effectively stimulate the calf muscles and tighten the calf. In general, the effect of indoor treadmill running is better than outdoor running, and the damage to the body is also lower. On the one hand, the speed of the treadmill is balanced, the body adaptability is better, and the physical damage is relatively minor. In addition, the running resistance of the treadmill is reduced, and the physical comfort is also better. […]