There’s always a huge debate on what’s the best repetition and the difference in men and women’s weight lifting and fitness. The truth is there isn’t, or at least, there shouldn’t be any debate. The difference in repetition offers difference in muscle development. So choosing the right repetition comes down to personal preference for your fitness desires. You’ll get results as long as you’re stimulating muscle growth by progressive tension overload, cellular fatigue, and muscle damage .
So which set of repetition is best for you?
Myofibrillar hypertrophy is the growth of muscle contractile parts. Larger fibers would increase force which means more strength and speed, so many call this form of growth the most functional. These components specifically involve very heavy weight for low reps performed between 4-7 reps range which will increase power . This will give your muscles a great defined look with a lot of strength with a minimal amount of size. This repetition range is more recommended for women who are simply trying to tone up and not bulk up. If your goal is to build mass this repetition set is not for you.
Sarcoplasmic hypertrophy is the growth of plasma, organelles, and non-contractile proteins which will increase endurance . Also known as “strength endurance continuum”  this may come from a demand for more glycogen and ATP. The muscles need to last longer with less need for maximum strength and speed in briefer periods. This would add to muscle volume, but not grow the fibers themselves for peak force as greatly. Sarcoplasmic is performed with moderate weight with repetitions in the range of 8-15. This will give you extreme size with very little strength. This is more for competitive bodybuilders than someone who is just trying to build a solid physique.
No matter what your fitness goal is working both muscle hypertrophy plays an important role. We would recommend throwing in a few sets of myofibrillar along with sarcoplasmic sets.
Or build the size you are happy with then switch to myofibrillar to continue training but focus more on strength. It’s really a personal choice on what you want to accomplish.