Acid casualty

The build-up of lactic acid in your muscles will add seconds to your lap times - unless you tailor your training to deal with it.

There's light at the end of the tunnel at last! Spring isn't too far off now and this barren time for UK motocross will soon be over.

We are very much in the pre-season period now as opposed to the off-season break and the various pro riders I work with are disappearing off around Europe in search of sun and sand (or both) to ride in, test new 2006 bits and get the bike time and fitness up.

If you have been training regularly over the off-season and keeping those fitness levels up now's the time to change things around to make the training much more motocross specific and prepare your body for the rigours of racing.

Motocross racing is high-intensity exercise as we know. As intensity increases, the body's oxygen supply struggles to keep up and continue to provide oxygen for respiration. There comes a point where one of the by-products of energy production - lactic acid - cannot be broken down and neutralized by the body and it begins to accumulate. Lactic acid builds up in the working muscles making it a more acidic environment. The condition is known as acidosis and it is experienced as the feeling of sore or 'heavy' muscles.

This obviously affects your ability to maintain your pace and on the motorbike you may feel this soreness in your arms, shoulders or legs. The pace has to drop and you are suddenly working your way backwards in the pack and just hanging on until that final lap. Acidosis also affects the way in which the muscle works and hinders its contraction-relaxation mechanism. This hampers co-ordination capacity and greatly affects technique - a big problem in a sport which is heavily influenced by technique and skill - so you start to ride poorly and get frustrated at your mistakes.

Fitness training for motocross is seasonal and has different components depending on the rider and time of the season. Hopefully you will have been following long duration and medium intensity levels of exercise over the winter so far. This will have helped your body burn fat as well as helping it become more efficient at taking in, transporting and using oxygen and started to change the make-up of your muscle fibres to be more endurance based.

Now that we are only six to eight weeks away from the start of competition we need to think about being in good condition and physically prepared for racing. The training done up to this point may not been seen as very 'event specific' - that is, it doesn't necessarily replicate the heart rates seen when racing. Now is the time for this!

One of the best ways to train specifically for motocross is to train at the intensity level at which lactic acid starts to accumulate in the muscles and acidosis becomes a limiting factor in your riding. This intensity point is generally known as the 'lactic threshold' level. For MX this is generally the intensity level at which you ride on the track at the start of the race - imagine how much better your results would be if you could maintain that intensity of effort and speed all race long!

* Training at this 'threshold' level will allow your body to cope with the build-up of lactic acid and allow you to not only maintain performance and speed when it builds up but raise the level of exercise at which it starts to build up - so you can go faster for longer.

* Find your ideal training range for this - it is usually about 90-95 per cent of your maximum heart rate or the equivalent level of exercise that you can just sustain for four to five minutes. These five minutes of very hard exercise forms one 'bout' of exercise and after a rest interval is repeated four to six times. This level of exercise will be higher than race levels if you can only just sustain it for five minutes in one go and will allow you to up your 'ceiling' and go harder for longer on the bike.

* You can use any piece of equipment to train in this way - cycling, running or rowing machines are ideal. Aim to lift your exercise level right up and keep it steady - using a heart rate monitor is very useful for this and you will soon learn the range which you can maintain for this duration. You can set a distance on the rower or a level/gear on the bike and maintain a set rpm for the duration of the bout.

* Two sessions a week of this high intensity training are ideal. Any more and you won't recover sufficiently between training sessions. Include one long steady cardio session and/or a weights training session into your week too to give a good pre-season training routine.

* High intensity exercise can be made more fun if there are a couple of you. Racing a friend of similar fitness to a set point - up a hill, through a park, round a track etc - will help you get the best from your training.

* Don't forget that this kind of training will also help your recovery rates. This kind of training will help you to go into the second (or third) race fresher than before.

* Lactic acid build-up has a negative effect on muscle movements. It has been shown that low intensity exercise following hard efforts helps reduce acidosis much quicker than just stopping altogether. Therefore in the rest interval walk, cycling slowly or perform the activity at a snail's pace. Now you know why some pro riders are straight onto the stationary bike in the awning after the race and don't just slump into a chair.

Hard efforts that lift your heart rates right up are the name of the game now - but only if you have been training up to this point. If you haven't you won't be able to just jump straight into this kind of training.

These efforts will be best in getting you all set for racing and help you push your riding levels, have more concentration and fun on the bike and enjoy the riding and racing more than just hanging on after five minutes!

Including other forms of training such as strength training and core work are also important so try to put together a balanced plan with the help of a trainer or through good understanding of your needs. It'll be worth the effort!

Alan Milway is a qualified sports scientist who runs MX Fitness specializing in training Motocross and enduro riders. For more information on how Alan can help you train go to his website www.mxfitness.co.uk or call him on 07810 827427.