LIGHT WEIGHTS OR HEAVY WEIGHTS, WHICH ARE BETTER FOR BULKING UP?

The usual advice when it comes to weights is straightforward. To tone up, use light weights and more reps. To bulk up and build muscle, use heavy weights and fewer reps.

New research is showing that this trusted fitness mantra may need some tweaking. What’s going on?

1.      WHAT MAKES MUSCLES GROW?

Building up muscles is actually an exercise in controlled damage. The skeletal muscles are made of thousands of fibres, linked by connective tissue which carries blood supply and connects muscles to bones.

There are thought to be two types of muscle fibres. Type 1 are ‘slow twitch’ for endurance, and type 2 are ‘fast twitch’ for anaerobic and explosive effort.

For most people, the number of muscle fibres is fixed, but their size can be increased. This mechanism is stimulated by loading the muscle, which causes tiny tears in the fibres.

2.      I’M TOLD THAT REST IS ALSO ESSENTIAL – WHY IS THAT?

Muscles actually grow when you stop working out. As you rest, the muscle fibres are repaired and will increase in size. To do this, the body needs a good dose of protein as well as a correct balance of other nutrients.

So you need to give your muscles time to recover in order to make them bigger.

3.      SO FAR SO GOOD – NOW WHAT SIZE WEIGHTS SHOULD I USE?

Here’s the clever bit.  It is the type 2 fibres that have the most potential for growth, but to do that you need to activate them.

The body uses the type 1 fibres first, and it is only when fatigue sets in that the type 2 fibres get involved.

So the type 2 fibres can be activated either by short sessions with heavy weights or longer sessions with lighter weights.

A small study has shown that either method will work, although bigger weights will build more strength.

Training to fatigue is the key. To do this, stop counting your reps and keep going to the ‘AMAP’ point. That stands for ‘As Many as Possible’ - a good target!

As always, look to your technique, choose kit that works for you and take advice from the professionals.