I'm sure it's a good use of time for many people. There's many benefits, I've just weighed them and determined for myself I'd rather use my time on something else. 45 minutes a day of working out equates to 5% of my remaining lifetime waking hours. I have ALOT of shit that I am trying to get done before I die, and the ROI on using 5% of it on this just doesn't make sense to me individually. Some personal reasons: 1) I see the value in an active lifestyle, I just don't see the value in working out or running around kicking a ball for the sake of it. My day to day activity is already active enough, my body has exactly as much muscle as it needs to deal with it's current workload. We build and maintain our buildings, we produce (and hunt) our own food, we maintain our roads, we cut our own heating fuel. Yes, we do this in as energy conservative a manner as possible, ie, we're not chopping firewood with an axe, but it's not a sedentary lifestyle. 2) I'm genetically of very small stature. I learned early that weight matters more than training and strength. I'm not saying that strength and training don't make a difference, I'm just saying my huge cousin who was just born a beast would beat me in a fist fight regardless of how much weight lifting I do. There are examples of highly trained people who would fight way above their weight class against average people, but I've determined that it would take a massive amount of effort for me to build up to a point that I could win in a confrontation without fighting dirty. I'd rather spend that time on IPSC, UDPA or some other defensive pistol training which I enjoy and has a higher likely hood of actually protecting me. If I need to carry a fridge up a flight of stairs, a have close family members that love to be asked for help, or hell, I can pay someone with the extra money I made using the work out time more productively. I'd probably have needed help even if I worked out like crazy my whole life. 3) Women prefer muscular guys, but I'm past the stage in my life where I care about attracting a mate. That being said, women are also attracted to power/authority and wealth. 4) If I value my time at $100/hour, that 45 minutes a day costs me $75/day. That's $27,375 I could have earned in a year if I just worked instead.