Yes, treadmill running is easier than outdoor running. In the words of John Post, the medical director for training Bible coaching explains that the treadmill absorbs a significant amount of impact, sparing your body. Also, he adds, The downside is that it doesn’t condition the shock-absorbing musculature of the lower extremities like road running does.”Though there are pros and cons, however for the movement of muscles and joints treadmill is a good idea and easier for the body.