I hate to say it. IT DEPENDS.
I see so many people at the gym who aren’t challenging themselves. They tend to stick to machines. They do high reps at low weight. Or perhaps only one set at a semi-challenging weight. They’re not really aiming to build more muscle and increase functional strength.
To those people, I say, “Go hard!. Lift 7 days a week if you want. It’s not gonna hurt. And it’s a damn sight better than sitting on the couch.”
But if your goal is to build/maintain a significant amount of muscle and maximise your functional strength, I’d say 2 or 3 days in the weight room per week can easily be sufficient — if you push yourself hard on those days and design the program carefully to avoid over stressing particular muscle groups.
Some key principles:
Compound Movements with Free Weights. Stick to compound movements with free weights as much as possible. I’m talking dead lifts, squats, bench press, overhead press, power cleans and snatches, pull ups, etc. These compound movements give you the most “bang for your buck” because they engage the broadest set of muscle groups, including the “stabilising muscles” that simply aren’t activated with machines. (That said, using machines and pulleys is perfectly fine if you can’t replicate a particular movement with free weights.)
Push It. Like I said, in each workout, PUSH YOURSELF HARD. Do a light warm up set (or two) for each movement, then add weight close to your max capacity for 5-10 reps per set. Do at least 3 sets.
Add Weight Over Time. Once you can bang out at least 3 sets of 5 with relative ease, add weight. Repeat over time in small increments.
Alternate Muscle Groups. Don’t stress the same muscle groups in every session. Many people alternate between “Leg Day” and “Arm Day” to allow distinct muscle groups to recover. But you can do it however you want as long as you’re not overlapping movements from session to session in a way that prevents recovery. Allowing your muscles to regenerate between sessions is essential to build muscle and gain strength.
Mix It Up. In between days in the weight room, perform other forms of exercise. Plyometrics, sprinting, yoga—activities that get the blood flowing into muscles that need healing and that challenge your body in ways weights don’t.
LISTEN TO YOUR BODY. If you’re lifting and it’s not feeling right—you’re tired or tight or just not feeling good—STOP. I can’t tell you how many times I’ve injured myself by ignoring these body signals because I was so intent on banging out my reps. Screw that. Particularly as you get older, you need to heed warning signs that today might not be the day to put up big weight. When that happens, work out a different muscle group that feels okay. Or perhaps do a lighter form of exercise that day.
As I’ve aged, I’ve learned that “less can be more” if the workout is designed appropriately. 2–3 days in the weight room per week can be plenty if you’re working hard and challenging a broad array of muscle groups.