Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great. Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great.

Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great. Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great. Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great. Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great. Yes, because of the angle and strength needed to climb the stairs, the legs and knees are much larger than when running, which makes the knees bear more friction. The damage is also great.