Cramp! And how to avoid it

We all know the horrible feeling of cramp.. it's that unbearable tightening pain that can occur in pretty much any part of your body and can often mean an end to immediate competitive efforts. By looking at the mechanics of cramp and why it occurs, we can tailor our training and nutrition to successfully deter its occurance in the majority of instances.

In order to understand cramp, it is first necessary to understand the mechanics of muscle contraction. The sliding filament, or ratchet theory, of muscle contraction refers to the binding of myosin cross bridges within the muscle filaments, to nearby active sites on actin filaments.

This reaction, which is stimulated by motor neurons carrying electrical signals stimulating the release of calcium ions, results in each myosin cross bridge flexing backwards at its hinges, pulling the actin filament with it (known as the power stroke). Immediately following this stroke the myosin cross bridge detaches its head from the actin site, tilts forward to its original position and reattaches to another actin site further down the filament. This process continues, pulling the actin filaments towards the centre of the myosin filaments and thus culminating in muscle contraction, or shortening. The energy for this process is supplied by ATP (adenosine triphosphate) which is supplied by mitochondria in the muscle cells.

Cramp is perhaps best explained by looking at the occurance of rigor mortis, or muscle rigidity, a few hours after death. Because a dead body is unable to resynthesise the energy molecule ATP, the calcium ions remain in the muscle cells and thus the cross-bridge bonding of actin and myosin remains (cross-bridge detachment depends on the synthesis of ATP). Cramp can be explained in a similar way. In the absence of sufficient ATP in the muscle or if there is inadequate re-absorbtion of calcium ions after contraction to promote detachment of the myosin cross bridges, the rigor complex will remain. If enough muscle fibres are affected, an entire muscle group, such as the quads or hamstrings, might experience 'cramp'. Not good!

So how can we avoid it?

- Warm up properly. Diving into maximum effort exercise without adequate mobility, movement preparation and muscle activation work will not only increase your susceptibility to injury, but it'll also leave you more prone to cramp. Don't think of your warm up as something you do before training. Utilise every minute - it will optimise everything else you do during your session!

- Stretch, but not too hard! Overstretching your muscles will activate the handy little golgi tendon organs (GTOs) in your muscles which detect overstretch and causes your fibres to contract - sometimes too much.

- Foam roll - rolling will increase blood flow to your muscle tissue, release adhesions and break down scar tissue which will compromise your muscles' functional capacity.

- Stay hydrated. Lack of water will affect every single one of your body's cellular functions, including muscle activity.

- if you are prone to gastroc (calf) cramping at night, ensure your bed covers arn't too tight; forcing your toes into plantarflexion (or pointing) will increase the risk of spasm.

- Eat a well balanced diet. If you don't know what this is or how to integrate it into your lifestyle, this will help!

- train your energy systems to cope with the intensity of your sport or activity, so that your body doesn't run out of ATP and go into spasm, or cramp. If you need help devising a program for your sport, why not book a 30 day trial with us at Phoenix Pro Fitness?