BODY SCIENCE
Mechanics Before Shoes
In recent years , there has been much debate regarding barefoot running and the various levels of cushioning found in running shoes , but running well and staying injury-free isn ’ t just about the shoes .
– BY ERNEST HOBBS , BIOMECHANIST
ssentially , if early man was barefoot while hunting , why are we encouraged to wear built up shoes ? And if shoes are more fitting for modern man , how much cushioning is best for
Erunning ? This is further argued when statistics suggest that injury rates among runners have not noticeably reduced , even though the technology of running shoes has changed significantly over the last few decades .
Heavily cushioned shoes have been found to promote heel-striking during running by reducing the pain experienced as the heel strikes the ground . However , the impact forces experienced when heel-striking may increase the risk of developing a range of injuries , such as shin splints and stress fractures . Barefoot running was suggested to discourage a runner from heel-striking , as the sudden impact on an un-cushioned heel would cause pain , resulting in a runner adopting a midor forefoot striking pattern .
The problem with this theory is that not all runners will change to a mid- or forefoot striking pattern , and heel-striking on an un-cushioned heel places a runner at even greater risk of injury than heel striking in a cushioned shoe . This emphasises the need to adopt a forefoot strike when transitioning to barefoot running , and highlights the importance of running mechanics , more so than running shoes only .
STRIKE PATTERN
Since running mechanics come first and running shoes come second , how does forefoot-striking differ from heel-striking ? Forefoot-striking involves a shorter stride length , with the foot making ground contact closer to the body . The knee is straighter at mid-stance and the foot makes contact with the toes pointing down rather than the toes pointing up as with heel-striking . With the knee bending less , the thigh muscles work less hard to absorb the impact of running .
Unfortunately , this means that the calf works harder to absorb the impact , increasing the risk of calf and Achilles injuries . Additionally , with the small bones of the forefoot coming in contact with the ground before the bigger heel bone , these small bones are also at greater risk of injury . Studies have found that runners with greater leg stiffness ( less bending of the knee and ankle ) tend to suffer from more skeletal injuries , whereas runners with less leg stiffness had a greater incidence of injury to the soft tissues , such as muscles and tendons .
Even though the appropriate running shoes are essential , it is more important to consider the striking pattern a runner uses . Running shoes are less likely to prevent an injury , but adjusting running mechanics and the foot-strike pattern may reduce the strain a runner experiences , thus alleviating pain and lowering risk of injury . Consult a relevant professional to determine the most appropriate approach , since each runner ’ s needs may be different .
About the Author Ernest is a biomechanical , video , and running gait analyst at the High Performance Centre ( HPC ) of the University of Pretoria .
• They contain vital vitamins and minerals , like vitamin C , potassium , folate and beta-carotene .
• They ’ re low in fat and calories , yet fill us up , so they help with appetite and weight control .
WHAT COUNTS AS A PORTION ?
Each different fruit contains various combinations of fibre , vitamins , minerals and antioxidants , so to get the best benefit , eat a variety of fruit daily , especially differently coloured fruits . Most fruit-containing foods can count towards your three fruit servings per day , but there is a limit to how many portions they provide , regardless of the amount . For example :
• Fresh fruit : 80g of fresh fruit equals one fruit portion , e . g . 1 medium apple , 3 apricots , 4 heaped tablespoons of blueberries .
• Dried fruit : 30g dried fruit equals one fruit portion , e . g . 2 figs or 1 heaped tablespoon of raisins .
• Tinned fruit : 80g tinned fruit equals one fruit portion , e . g . 2 pear halves or 2 pineapple rings
• Fruit juice : A small glass ( 150ml ) of pure fruit juice counts as one fruit serving , but you can only count one serving of fruit juice towards your three fruit servings per day . This is because unlike fresh fruit , the juicing process squeezes out natural sugar that is normally found between the cells of fruit , which is harmful to your teeth .
WEIGHT-GAIN WORRIES ?
Many people make the mistake of thinking fruit is sugar and will cause you to gain weight . The truth is , fruit is made up of various types of sugars , but the main type is fructose , which has a different metabolic pathway and a lower glycaemic ( blood sugar ) response compared to glucose , which is found in candy and sweet , refined carbs . Fruit also contains fibre , which lowers the glycaemic response even further . Thus if you eat a lot of fruit at one time , the sugar load in the blood can rise unfavourably , but not if you eat one to two portions at a time . The key is to have a variety of fruits and spread them out throughout the day .
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