How long is the duration for which we are required to rest after workout. Is it good to do 2-3 sessions of heavy workout every day? What should be the rest period between the two sessions. I take 1 gm of proteins per pound of body weight. How I am I supposed to keep up my energy if duration of both sessions is 100 minutes?
It's all genetic for the most part. It has nothing to do with whether or not you're a rare, one-of-a-kind elite pro athlete that comes once in a generation; or if you're a couch potato who can't lift 100 lbs.
How long you need to rest and recover varies and depends based on each person and how much you prefer to recover before loading again. I know of at least one guy who trains 6-7 days a week and it works perfectly for him (and no, he doesn't use pro-hormones). Why? Apparently he recovers faster.
Some people take longer to recover, but nothing stops you from jumping the gun. As far as I can figure you can't reduce gains just by jumping back in a little quicker -- just don't workout constantly.
In general, most people recover enough in 48-72 hours or less for more loading, but the point of diminishing returns depend on how much intensity. See, you can lift 7 days a week and curl paperback for 300 reps and I doubt you'll have diminishing returns -- but if you try and power curl 90% of your max every day you just might see no advantage. Interestingly, sleep helps repair muscles. If you just simply sleep more while maintaining a good diet you'll definitely see muscle repair faster.
If you spend an entire 24-hour period sleeping 80% of the time and eating the rest you'll probably recover enough to jump back in immediately the following next day, fresh as a water buffalo.
Three things you should know/focus on:
1.Intensity. If you do an extremely intense workout, odds are you won't recover the next day -- so give it several days at the minimum, unless you feel perfectly refreshed sooner. If you do low-intensity workouts, do it more times per week, possibly splitting up the days you do it if you prefer.
2.Recovery is genetic, but sleep helps. If you want to workout more and get stronger faster, consider sleep supplements if you're not a naturally good sleeper. Also, remember that good sleep is at least 9 hours (with REM) -- no less or you're slowing down recovery.
3.Calories and protein help recovery. This doesn't mean eat non-stop, but it does mean that you should eat every 4-8 hours, and shouldn't let your net negative energy balance stay below -800 for more than 10 hours at a time. Most meals should be small-ish but packed. Spread your calories and do not simply think you must always be in a surplus/deficit -- don't think in extremes because the world doesn't operate that way. Consistent eating replenishes muscles and helps them recover, so try and eat well consistently but do not over/under eat. Good luck and may you grow powerful like me.
For all but perhaps a few elite professional athletes, multiple heavy (intense) workouts per day are not good/useful, because they almost certainly cause more fatigue than that from which the body can recover within one day (or possibly multiple successive days).
Note that insufficient recovery usually prohibits the desired adaptation (for example, increased strength), so exercising more (that is, incurring more fatigue) does not necessarily increase strength -- it actually may decrease strength.
I would say that 2 - 3 sessions of heavy work every day would be too much, but then with adequate nutrition and recovery, I imagine even that can be adapted to.
It all comes down to what your goals are.
I know of a few weightlifters who train multiple times a day, but these are people who compete at a national level, and by necessity, training for weight lifting tends to involve lots of sets of low reps, especially for the more skilled movements (snatch, clean and jerk).
Some old school bodybuilders used to train twice a day, morning and evening, with pretty full on sessions both times (names escape me at the moment, but T-Nation has posted a few articles on some of these guys).
The Squat Every Day program gained some traction a year or so back (I've fallen out of touch, so maybe it still has some), the idea being that you work up to your squat max every day, and once you get over the initial week or so, your body gets used to it.
For skilled movements, and arguably for pure strength without a lot in the way of hypertrophy, training multiple times a day can be very beneficial. Suck at pulls ups? Then do multiple sets throughout the day and watch your strength increase. This is commonly known as Greasing the Groove and from my understanding trains the CNS to more efficiently recruit the muscles required to carry out the movement.
Research shows that you can get incredibly more size and strength gains by doing heavy training everyday compared to doing it 3 times a week(1) (At equal volume)
Further, a 2017 meta-analysis of 15 different studies published in theJournal of Sport Science(2) said:“Results showed an incremental dose-response relationship whereby progressively higher weekly training volumes resulted in greater muscle hypertrophy.” This indicates training body parts more often is ideal for building muscle because of this in part, means a higher training volume overall. When you spread your training volume out throughout the week your muscles will have more time to recover and grow between workout sessions.
Not only does training more often gives better gains at equal volume but training more often actually allows for greater volume over time, and volume is the is directly related to the amount of muscle and strength you can build.