Would working the same muscle group - twice in the same day - cause worthwhile extra muscle fiber tearing to later gain mass? Or is this not worthwhile (the extra tearing is only marginal) given the long rest period between the two sessions (say morning and evening)? Why?
Example: working the upper and mid chest in the morning, and again in the evening, working to failure both sessions using high reps and moderate weight. There will be rest for that group for the next couple days, and proper diet is regularly followed.
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