Since the age of 17, former national bowler Lesley Low has been living with inward-rolling feet and flattened foot arches.

"It's been giving me shin splits, and it really hurts," says the 20-year-old of her pronated feet.

Lesley is not alone.

More than 70 per cent of people excessively pronate when walking on firm ground.

Our feet were originally designed to walk on soft, natural surfaces like sand and soil, says Dr Phillip Vasyli, an award-winning podiatrist from Australia.

"However, in today's environment, we subject our feet daily to hard, unforgiving surfaces like pavements and floors," he adds.

As we take between 5,000 to 8,000 steps a day, the forces that are experienced during walking are repeated constantly, placing unwanted stress on the feet.

Our feet pronate to absorb the shock - a natural and necessary reaction.

However, excess pronation is a serious problem as it disrupts foot function and knee alignment. It also tilts the hips forward, increasing the curvature in the lower back.

"If left unaddressed, it can cause the foot's soft tissue to become inflamed, causing acute discomfort. In the later stages, osteoarthritis and various bone deformities can develop," says Dr Vasyli.

The most common foot problem is heel pain - medically known as Plantar Fasciitis.

Footbeds and cushioned insoles are often used to relieve such pain, but they only address the symptoms and not its cause, warns Dr Vasyli.

Although prescription orthotics provide proper support, they are pricier.

A good alternative - that's also easier on the wallet - is the new Scholl Biomechanics range, developed by Dr Vasyli.

Priced from $26.90, these non-prescription orthotics promise to adjust foot posture and alignment, while minimising stress on the feet.

Although such over-the-counter products help in addressing problems caused by excess pronation, you should see your doctor if pain persists.

Good shoes

It is also important to wear shoes that are healthy for your feet.

Slippers - a perennial favourite among Singaporeans - are a bad choice of footwear because their flat footbeds that do not provide support.

Part 2: Four types of shoes that are bad for you

The Scholl Biomechanics range is available at selected Guardian Pharmacies, Watsons and Unity.