The Benefits Of Strength Training For Runners

There are two types of muscle cells or fibres which reside in our muscles and they are randomly mixed in all of us. Type 1 is red in colour with a high content of myoglobin, the protein involved in transference of oxygen to the mitochondiria and acts as an oxygen store within our muscles. Type 2 is white in colour and has a low myoglobin count. Type 1 muscle fibres are defined as slow twitch (ST) and type 2, fast twitch (FT). Type 2 muscle fibres contract rapidly as there is high myosin ATPase activity. Type 1 muscle fibres have lower myosin ATPase activity so contract at a slower rate.

Although these two different types of muscle fibres are found predominantly in our muscles there are varying grades between the two in each of us. An athlete could have type 1 muscle fibres which contract nearer the speeds of type 2 and vice versa. So, lets look at the two different muscle types using sprinters and endurance runners as examples. Sprinters have a predominantly high level of type 2 muscle fibres in their muscles (fast twitch), compared to middle distance runners who are more likely to have equal amounts of type 1 and 2. Long distance runners have been shown to have predominantly type 1 fibres (slow twitch).

Sprinters are designed to be big, muscular and powerful in order to achieve explosive bursts of speed. They are however, unable to sustain such effort for longer than 20 to 40 seconds.
Distance runners are small but still powerful and have a large capacity for transporting and utilising oxygen. This is very important, though not as essential as fatigue resistance.
We already know that sprinters have an abundance of fast twitch type 2 muscle fibres while their counterparts; distance athletes have fatigue resistant type 1 muscle fibres.
Recently in the two disciplines of sprinting and long distance running Africans have the best overall sporting performance of any other continent. West Africans (Senegalese, Liberians, Nigerians and runners from the Ivory Coast) are the best at sprinting and North/East Africans (Kenyans, Moroccans and Ethiopians) the best at endurance running. This is thought to be attributable to genes mostly, but with sports science still studying this interesting phenomenon, we have yet to find out exactly the reasons for Africans from these parts dominating running events across the globe.
Tests have been conducted on endurance runners and sprinters to see who are the healthiest overall. It appears that distance runners are the healthiest throughout their life compared to sprinters, which suffer more from high blood pressure, diabetes and obesity.

Tests show that Type 1 muscle fibres found in thighs are thought to influence fitness, chosen levels of physical activity and cholesterol concentration. Athletes with more type 1 muscle fibres are thought to be more physically active and have a better cholesterol reading throughout their lives than type 2’s who were negatively influenced towards inactivity and coronary heart disease. Type 1’s remained fitter and leaner as those with more type 1 fibres tend to have low body fat levels. They burn more fat as fuel when they exercise which is also thought to enhance performance levels. Type 1’s are thought to have a natural ability in physical activity. Type 2’s are thought to have probably given up their sport such as weight lifting or sprinting as they got older while type 1’s carried on distance running throughout their lives.
Future science is leaning towards endurance runners testing for equal numbers of both type 1 and type 2 muscle fibres (like middle distance runners). It is thought that endurance runners who excel at marathons do so because they are slightly too slow for middle distance running. They had too few type 2 fibres.

It is now thought that equal amounts of both types of muscle fibres are needed to achieve faster times in marathon running. African distance runners are cases in point. In the future it is believed that a fast marathon win will not be won by somebody who has few type 2 fibres.
Logically for the future, optimal training for endurance running should include all types of running intensities so that all muscle fibres (fast twitch and slow twitch) are trained equally. This is why experienced and successful runners use interval training and fartlek techniques and also cross train with weights too.
Weight training uses mainly fast twitch muscle fibre type 2’s but causes muscles to enlarge without an increase in muscle fibres. Important benefits are made when weighs are lifted regularly including prevention of loss of bone strength and minerals, which naturally decline with age. Runners who only ever train their legs will also benefit from training their upper body. Training quadriceps muscles as well aids running performance as reduces muscle damage. Many runners believe that the way forward is to both train by running and also weight lifting, thus using both muscle fibre types.

Explosive strength training (weight lifting) may improve short ground contact time, which is imperative to producing quick speeds with rapid force. Exhaustion during 10km races was found to be due to increased ground contact time.
However, if you only wanted to strength train with weights it would be unwise to run as well. Running impairs the muscles ability to adapt to strength training. In contrast, if a runner wished to improve their performance between 5 to 90km, weight training has been found to be advantageous. The stronger you are the better you will perform at endurance racing.
The sprinter very quickly accumulates an ‘oxygen debt’ by performing at an anaerobic level, which is impossible to maintain for any length of time. The glycogen inside the muscles depletes and you become tired and stiff due to the build up of lactic acid. In order to start to function again the lactic acid has to be turned back to glycogen. Some athletes are able to do this successfully while distance running but that is another article!
Success in distance running can be determined by each individual’s ability to transport oxygen to exercising muscles. So, in effect you are conditioned by your genes, but you can choose to train at an optimal level, which includes using fast twitch muscles in order to enhance your performance.