If you are above these body fat percentages I recommend focusing on maintaining it over this holiday season, but still lift to build. Eat as clean as possible knowing the Holiday parties will negate your good days resulting in maintenance over the season.
To ensure muscle gain, us an intense program and one that you are not used to
A rep range you are not used to: Do 3-5 reps if you always do 6-12 as in the hypertrophy range. Also 15-20 reps work great for lower body hypertrophy.
Slow eccentrics: Doing a slow “negative” portion of the rep is proven to increase muscle size.
Very high volume: Most are used to 3x10, 3x8, 4x6, etc. Try 10x10 or 8x12, just keep the exercises to a minimum.
Strength/power supersets: Superset a strength exercise with a power exercise. Ex: Squats/Box jumps, Bench/Explosive pushups, Lunges/Explosive step ups, Deadlifts/Kettlebell swings, Rows/Explosive pullups.
Lift to failure or do forced reps(partner assisted reps) on half your sets: Simply upping the intensity to this point is something many people don’t want to do or can’t because it requires a workout partner.
These are all great ways to build muscle, but they should be used in phases like any intensified program. 3-4 weeks is enough, then move on to something else. Some may find it hard for their bodies to handle very high volume or forced reps so shorter duration of these phases may be needed.
Don't worry about losing body fat in December
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2) Kraemer WJ, Ratamess NA. Fundatmentals of resistance training: progression and exercise prescription. Med Sci Sports Exerc. 2004 Apr;36(4):674-88
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