After doing some research, I am very skeptical about the low-reps plan while trimming down.
Well, let’s see:
Type I fibers are very insulin-sensitive, followed by type IIa. Type IIb are insulin-resistant.
Type I fibers are the most oxidative, followed by type IIa. Type IIb fibers are NOT efficient at oxidating fats for energy.
Type IIb fibers have been shown to be associated with propensity towards diabetes and obesity.
I will give all the references if asked.
Considering these factors it seems clear focusing on developing type IIb fibers while trimming down while neglecting type I and type IIa fibers will NOT put your body in a mode where it’s as efficient at burning fats as it can be - nor as insulin-sensitive as it can be.
As such I am now recommending training which boosts type I development and favors changing type IIb fibers into type IIa fibers for those who are not interested in powerlifting or explosive activities of short duration.
It is my opinion that low rep work is not only NOT efficient, but actually prevents the best results in terms of BODY COMPOSITION improvement.
As far as muscle gain goes, again it improves the neuromuscular efficiency, but it’s not enough time under tension to promote considerable hypertrophy when compared with a bodybuilding type of program.