Cushioned running shoes increase the risk of foot injury and leg pain, say scientists

Cushioned running shoes alter the natural spring-like mechanism in a runner’s leg. This ensures they bend their knees and ankles to create a bounce movement. Altering this causes runners to land with a stiffer leg, which can lead to injuries

Man-running-2

Wearing cushioned running shoes may actually increase the risk of foot injury. Trendy running shoes put more stress on bones, muscles and joints rather than less. Joggers may be more likely to develop plantar fasciitis, a condition which causes a stinging pain in the foot.

Although many opt for comfy trainers to prevent injuries, the cushioned running shoes may do the exact opposite. Scientists say that the trainers (running shoes) put more stress on bones, muscles and joints rather than less.

This means joggers are more likely to develop plantar fasciitis: a stabbing pain in the foot, or tiny fractures in the shin bone, or tibia.

The research was carried out by the University of Helsinki and led by Dr Juha-Pekka Kulmala, a clinical biomechanist.

Running has significant benefits for a person’s heart and overall health, however, between 37 and 56 per cent of joggers experience injuries every year worldwide.

These injuries are thought to largely occur due to the vertical force that is created when a runner’s foot hits the ground.

To reduce this, many trainer manufacturers have added cushioning to their shoes’ soles, however, there is no evidence that this actually prevents injuries.

For the study, a few participants completed a 3D running analysis while jogging in the shoes at 10km/hr and 14.5km/hr.

Results surprisingly revealed the runners’ feet hit the ground harder when they were wearing the cushioned trainers. This was particularly true at 14.5km where the load impact was 12.3 per cent greater than in the regular trainer.

A video analysis showed the runners bent their knees and ankles less when they wore the cushioned shoes, which caused their bodies to slow down quicker and placed extra stress on their legs. The study was published in Scientific Reports.

Humans are thought to have a natural ‘elastic leg behaviour’, which acts like a spring that shortens and lengthens with every step, and helps to create the bouncing movement of running.

This natural behaviour may be reduced in cushioned trainers due to runners subconsciously maintaining a stiffer leg to keep the same bouncing movement. This then causes them to bend their knees and ankles less.

This extra leg stiffness means that running in highly cushioned trainers will likely increase the risk of injuries, particularly stress fractures, the researchers warn. They add, however, further studies are required to confirm this theory.

The findings only apply to runners, with walking causing less of a vertical impact and therefore less cushioning likely being required, Dr Kulmala said.

Dr Kade Paterson, a podiatrist at the University of Melbourne, agreed more research is needed.

She told the New Scientist: ‘As a sports podiatrist, I’ve seen patients who’ve reported improvements with maximalist running shoes and others who’ve got injured in them so there probably isn’t a one-size-fits-all approach.’

Dr Paterson added the results do not suggest runners should ditch cushioned shoes entirely and said ‘like many health-related things, we should be somewhere in the middle’.

Dr Kulmala has previously warned about the trend of barefoot running, which he only recommends if you land at the front of your feet. Most people land on their heels, which creates a larger force and therefore needs more cushioning, he added.

Is it better to run barefoot?

Professor Pollard, a kinesiologist and a licensed physical therapist, said it is a first step in gathering evidence on the effects of maximal running shoes on injury risks.

Maximal shoes are becoming very popular, but without controlled studies, clinicians have been unable to make science based recommendations to runners.

Previous research has suggested cushioned running shoes have changed the way in which many of us run.

Using slow-motion footage, a previous study found experienced barefoot runners land very differently from runners who wear shoes.

The former tend to strike the ground with their forefoot or mid-foot, and the latter their heel.

So barefoot runners could be at less risk of certain types of injury than those who wear cushioned running shoes.

Striking the ground with you heel is like someone hitting your heel with a hammer with up to three times your body weight, said the Harvard University researchers.

Source: Daily Mail Health