Living without gravity has consequences for the bones and muscles. To counter that astronauts have to do exercise and lifting regularly when they go to the ISS.
Now are there any plans to counter this for people expected to live several years on Mars if they want to return to Earth?
Mars has gravity, so adverse effects may be less than spending the same amount of time on the ISS, but day-to-day activity in Mars' reduced gravity will certainly not load the body as much as activity on Earth.
This might be a dumb idea, but could using clothes made heavier in purpose all the time help?