“Why is it so hard for me to gain weight?”

The answer to this question can be down to a variety of reasons.  Of course, one of these is genetics.  Genetics plays a part in our capacity to gain and lose weight.  There are three main types of muscle fibres.  Everyone has a mixture of all three but one type is usually predominant in each person.

The three main types of muscle fibres:

1. Type I
2. Type IIa
3. Type IIb

Let us examine these three types of muscle fibres.

Type I – Endurance type athletes have lots of Type I muscle fibre.  It consists of slow twitch, oxidative fibres that are resistant to fatigue.

Samuel Wanjiru of Kenya.

Type IIb – Sprinters and weightlifters usually have a lot of this type of muscle fibre as their sport requires a tremendous amount of power and quick energy.  It consists of extremely fast twitch muscles that fatigue easily.

Yegeny Chigishev of Russia.

Type IIa – This is the middle ground between the two previous muscle fibres.  Middle distant runners and swimmers would benefit from having a lot of this muscle fibre as they need a fair amount of explosive energy as well as endurance.

Michael Phelps, USA.

If you find it difficult to gain weight this could be because you have a predominance of Type I muscle fibre.  This post is not to discourage you in your quest to build muscle but to give you a realistic expectation of the progress you can expect to make.  As long as you train consistently and properly you can overcome any genetic limitation.