Id's say a stronger circulatory sistem. Muscles and bone density will need to increase, but we do that as part of adaptation, evolution will favor the trait lo

Id's say a stronger circulatory sistem. Muscles and bone density will need to increase, but we do that as part of adaptation, evolution will favor the trait long term but regular use will already compensate in part or totally the need. Possibly ankles and knees will need to get stronger as well