in relation to this question below:
possible paths to increase bench press from 140kg (308 lbs) to 160 kg (352 lbs) - for 1o reps
rest time which is around 48-72 hours at the level you are, or which ever break suits you.
why exactly lifting heavy (at least 1.5 x body weight) makes us require more resting\recovery time?
Does it also change the metabolism?
“why exactly lifting heavy (at least 1.5 x body weight) makes us require more resting\recovery time? “
First off, it's hard to quantify the exact amount of recovery time on an individual basis. There are many factors that will affect recovery including genetics, nutrition, training status (newbie vs. experienced), sleep, fatigue, etc. While it is generally accepted that the recommended guideline for recovery is 48-72 hours, it is only a guideline. Individual rates of recovery vary depending on some of the factors I've indicated.
In their paper, Recovery in Training: The Essential Ingredient , doctors Jonathan N. Mike, M.S. and Len Kravitz, Ph.D. Explain:
“The greater the stress of the workout, the greater the overall muscle recruitment, and the greater the potential for muscle damage and soreness, therefore the need for longer recovery time. Muscle recovery between resistance training sessions for most individuals is also influenced by other types of training performed, such as cardiovascular training, interval sprints and sports conditioning sessions. “
And, paraphrasing from one of their sources, they indicate:
“Rhea (2003) concluded that for untrained individuals and trained individuals a frequency of 3 and 2 days, respectively, per week per muscle group is optimal, which translates to 1-2 days rest between sessions. However, this will vary depending on total volume of resistance training, individual training status, and overall goals (e.g., training for hypertrophy, strength, endurance, etc.).“
There's no indication in any of the literature that metabolism is directly affected.
It's called recovery, which means your muscles are recovering from any possible damage and fatigue from the lifting. They need a break to be ready for the next lifting. What do people usually say, when you have a very stressful day?It's, "I need a break". The problem with muscles is, they can't speak for themselves, so there are guidelines to follow, in order to keep them in good condition and help them recover and grow. In that break time, they undergo repair and get nourished and grow stronger. If you keep straining them heavily everyday, that would hinder the repairing process and as a result, they will fail. That's what you call injury.
The exact reason you require more time for recovery as you get stronger is easy to see if you consider the difference between an untrained man with a 12 inch pipe-stem for an arm and a well-developed bodybuilder.
Mr. Pipestem, when he does curls, is forcing a small and weak muscle to work very hard. Mr. Huge if he does the same thing is causing a huge muscle to work very hard. For Mr. Pipestem, the cost to his recovery system is small, to Mr Huge the curls represent a bigger cost to his recovery system.
You're ability to recover from exercise might go up 50 or even 80% from your untrained baseline if you become very fit. But youre ability to generate that cost may double or even triple as you get stronger. Your ability to generate bigger stressors to your body by improving the strength of your muscles outstrips your ability to improve your ability to recover.
That's the issue in a nutshell. If you're big and strong and work out very hard, you've really imposed a very large burden on your underlying metabolic system which gates your recovery rate. That's a bigger burden than you did when you were not so strong, relative to that same recovery rate.
HTH.
