Being a fit and strong 40+ year old person is not a difficult long-term goal. As the body ages, it is not as responsive or swift, but it can learn. The biggest mistake people make when it comes to their age and working out is allowing themselves to fall into one of two extremes: Completely ignoring that their body changes or believing that they can't work out because of their age, Caitlin Bailey, ACE Certified Personal Trainer and fitness instructor at PhilanthroFIT Training, says. “The best workouts for people over 40 would include multi-joint, compound exercises such as squats combined with a shoulder press,” Bailey says. “Also, a good balance between cardio and strength training workouts with dedicated days for recovery,” she adds.