This is a million-dollar question. How much should you train? There has never been a set limit because everybody has a different body type and a different response to a stimulus. But there are some generic benchmarks and guidelines for everybody.
1. Study and understand your body
As you grow old, your stamina decreases. The younger you are, the less effort you have to put into the workout. You must have seen 21-year-olds playing basketball/football effortlessly with their crazy stamina. That’s how it is; you won’t find the same energy in a 40-year-old. The good news for those who have been playing sports is that they thrive more on training with greater frequency than those who did not. Don’t beat your body about it; it’s not the body's fault.
Your body needs to be experimented on and then evaluated. Feel free to experiment with different training regimes and workout (under a trainer’s supervision) to see what works best for you. The human body is simple and complex both at the same time. You just need to figure out what your body responds to.
2. Duration of the workout
You must train different muscles every day, not overdoing any muscle and giving it enough time to recover. Each muscle needs 30-45 minutes except for your back and legs, that too because of their size and complexity. They should not exceed 60-70 minutes. Any other muscle should not take you more than 45 minutes to train.
If you are routinely crossing this limit then you are doing two things, tiring the muscle and wasting a lot of time between the sets or doing far too many sets than your actual body requirement. You don’t need 5 minutes rest between the sets unless you’re a powerlifter. You should move quickly and actively between the sets, keeping up the pump.
Pro-tip: To improve efficiency you can preset your playlist and not use your phone when working out. Save that time and start the next set asap!
3. Know when to stop
Yes, it is good to push through your limits but, that does not apply to workouts! Sometimes less is more; you don’t want to end up with an injured or fatigued muscle. You can’t always go by fatigue even if you’re using pre-workouts or energy boosters. There comes a time when your body starts telling you that you’re crossing the limit. Listen to it and stop! It’s alright.
You can try again after some time or maybe some other day. When it comes to exercising your arms, there comes a point when you’re getting all your reps and still have energy but you start losing the pump, that’s where you should stop and end the workout. Similar is the case with other body parts, observe and listen to your body. It’s always about being safe than sorry!
4. Never be afraid to take an extra ‘Rest Day’
People who go to gym or workout at home become a different breed altogether. Most of them dread working out and will find an excuse to skip the workout, while others won’t let anything come in their way. If you’re still reading this, you’re probably the second type. No matter what the weather is like or how busy you are, you always squeeze in some time for your workout. Your consistency is what separates you from the rest.
That can also go against you since you’re not taking off from the gym even when your body is telling you that it needs rest. Pay special attention to your energy levels and your enthusiasm for training. They are the only healthy indicators that will tell you if you are overtraining.
Never worry that a day or two will set you back or affect your energy levels. Remember, progress shows when you’re well-rested and fresh. If you still can’t resist going to the gym, do some light stretching, a little cardio but do not lift. This will give your muscles a nice rest and prep you for a hardcore session the next day.