Are you referring to boxing training for people over 65? I’m not sure this is something I would incorporate into this age group. Many of them have other issues that working out comes with great effort, limitations and commitment. For those who are in great shape I think incorporating some boxing routines into their workouts can be beneficial, but it must be examined case by case. Also many of them suffer from various medical conditions and HIIT programs like boxing might not be the best solution (of course their are exceptions to the rule).