An immense amount of recent research has reinforced the fact that exercise is essential for those who live with diabetes – at whatever stage you are – pre-diabetic; diabetic on diet + exercise only; diabetic on diet + exercise + tablets; diabetic on diet + exercise + tablets +/or insulin. This makes sense because we know that exercise helps ‘switch on’ insulin receptors in those with Type 2 diabetes, therefore is useful in lowering blood sugar levels.

There are also benefits of regular exercise of the feet, such as improved blood circulation. Blood contains oxygen, nutrients and repair cells so it’s vital that increased blood supply reaches each cell in the body, especially nerves and other structures in the feet, which are furthest away from the heart.

SA research

As part of Louise Stirk (a South African podiatrist) master’s degree, she studied the effects of an eight-week endurance exercise programme on blood sugar control and peripheral sensory neuropathy in people with Type 2 diabetes.

Her study was conducted on eight previously inactive diabetic volunteers, aged 34 to 47 years. They completed an eight-week endurance exercise intervention of moderate intensity. They started the exercise programme at the same time as two control groups. The first control group, aged 45 and 46 years, continued with a sedentary (inactive) lifestyle and the second active control, aged 40 years, continued with a prior exercise programme.

All participants were requested to maintain their usual diet. The moderate exercise for the previously inactive group consisted of a 30-minute cycling regime, during which the heart rate fluctuated between 60-80% of age-predicted maximum, repeated three times per week.

She measured the effects of this endurance exercise programme on diabetic peripheral neuropathy (DPN) and possible associations between exercise-induced changes in resting heart rate, blood pressure, body mass index, waist circumference, % body fat, six objective neurological measures of diabetic peripheral neuropathy, and eight subjective ratings of symptoms of foot discomfort. She also measured changes in HbA1c, plasma brain neurotrophic factor and serum adiponectin concentrations in all 11 participants.

The only significant change (p>0.05) in the passive (non-exercising) controls was an increase in subjective ratings of foot discomfort, while no significant change (p>0.05) was observed in the active control.

The eight-week endurance exercise programme was not combined with dietary intervention so it did not improve HbA1c levels, but it did result in significant improvements (p<0.05) in the average resting heart rate, systolic blood pressure, and patellar and ankle reflexes in the group of eight people.

Common reasons for not exercising

The most common reasons as to why diabetic patients don’t exercise on a regular basis is: their feet or legs hurt, they don’t know what shoes to wear, they don’t know how to exercise, they feel it isn’t safe to walk outside or they can’t afford a gym membership.

1. Feet or legs hurt
You may have an imbalance of the feet due to the effects of diabetes on soft tissue, or because of incorrect footwear or other biomechanical reasons of which you may be unaware. Feet should never hurt – this is a sign that something is amiss.

A podiatrist will conduct a full clinical biomechanical examination or you may choose to go to a biokineticist for a full-body assessment if other parts of your body also hurt when you exercise. Take your exercise shoes as well as your usual shoes with you to be assessed.

If imbalances or bony protrusions are present in the feet or ankles, a podiatrist will then take an impression of your feet in plaster of Paris or orthopaedic foam to fabricate custom foot orthoses, which fit into your shoes.

These can re-align your feet to make muscles work in balance with each other, offload sore spots or high pressure areas, and make you comfortable in your shoes once more.

Custom inserts, made by a podiatrist, can be moved between pairs of shoes and, even sandals, with a piece of adhesive Velcro affixed underneath to prevent sliding.

Do custom shoe inserts really work? 

In July 2005, James Wrobel, Adam Fleischer, Ryan Crews, et al., reported in the Journal of the American Podiatric Medical Association on examining the outcomes of custom foot orthoses on patients with plantar heel pain.

These researchers randomised 77 patients with plantar fasciitis to one of three groups in a double-blind fashion (custom foot orthoses, prefabricated orthoses, and a sham). Using objective and subjective outcome measures, they found a 5,6-fold increase in physical activity and improved outcome measures with the custom foot orthoses in comparison with the other methods at three months.

2. How to exercise feet

The second largest pump mechanism of blood in the body (after the heart) is that of the calf muscle ‘pump’. When the calf muscles contract, they push up against the big blood vessels deep in the leg.

Any exercise that helps the calf muscles to contract is a good exercise for lower limb blood circulation. Walking is excellent – choose a flexible pair of shoes that grip the back of your heels, and grip over the top of your foot with adjustable fastening.

If you have never exercised, start with a 5-minute walk then turn around and go back and you’ll have completed 10 minutes. The next day, increase by 5 minutes. The day after, increase by 5 minutes, or stay at the same number of minutes for a few days until you feel you can add on more minutes.

Motivating tip: If you are new to exercising, do not measure distance when walking as it will only discourage you, only measure by time spent. As you become fitter, you’ll naturally increase your distances. Work up to 30 minutes of exercise every second day, then eventually 30 minutes every day.

3. What shoes to wear

You need flexible flat soled shoes/takkies that have a good grip on your feet, either in the form of: laces up the foot or sturdy Velcro straps up the foot. No open back shoes. If you want to walk in hiking sandals, wear a pair of socks together with the hiking sandals to prevent chafing or blisters. Other types of fashion sandals are not suitable.

Make sure the shoes are wide enough for your feet. The easy way to check this, is to remove the innersole from the takkie and stand on top of it as if your foot was in the shoe. If your foot width spills over the sides, the shoe is too narrow for you and should be avoided.

New Balance and Asics now have sports shoes available in wider fittings, called 2E and 4E.

Be aware that your foot volume naturally increases by 7% after four hours of standing or walking, so allow for foot expansion when fitting.

Make sure the shoe is flexible – you should be able to bend it back from the ball of the foot with one finger. If it is not flexible enough, the calf muscles can’t work to their full capacity because the foot can’t bend easily at the ball of the foot.

4. Can’t afford gym or scared to walk outside?

Here are simple ways to exercise feet in your own home:

Sitting: Sit up on a chair with your feet flat on ground and knees bent to 90 degrees. Keeping your toes on the ground, lift the heels off the ground then put them down. Increase the number of repetitions until the calf muscles feel tired, then stop.

The next day, try to increase beyond the previous day’s number of repetitions by 1, the day after by 2, the day after that by 3. That way you will gradually build up to being able to do 300 repetitions while watching TV, or sitting in the office, or waiting at an appointment.

Standing: You can do calf raises holding onto the back of a chair, or the supermarket trolley, or while waiting for the kettle to boil or the photocopy machine to do its work.

On your bed: If the weather isn’t good, you can still lie on your bed and do exercises pointing your toes away from you and then pointing them towards you. Do at least 100 repetitions or until your calf muscles ache. If you persist with the exercise each day, it will become easier to do and the aches ease up as you improve your blood circulation.