No one has ever asked me what to wear for exercise. I suggest that people wear what they are comfortable in if they do not have “exercise clothes”. Not everyone has sneakers, so, I do suggest those.
It comes down to personal preference and safety to get the client comfortable enough to stay with their exercise program.
not if you word it that generally. But there are certain activities for which specialty apparel has a place. Well-fitting shoes are a must if you want to run, even if it is on a treadmill. If you like to strength train at a gym, make sure that the clothing does not restrict but also cannot get caught on equipment.