It states on the National Institute of Diabetes website that most people who are suffering from insulin resistance don’t realise that they have the condition until they eventually develop Type 2 Diabetes.
This is a scary thought when you consider that around 4 million people around the UK are currently suffering from Type 2 Diabetes, add to this the number of people who have undiagnosed insulin resistance and that number could, and almost certainly will, considerably rise in the near future unless there are drastic changes to the way that we each approach our individual health and well-being. So what should we be doing to recognise this condition early on and prevent it leading on to Type 2 Diabetes?
Well, the ‘good’ news is that much of science now points to our own lifestyle choices as being the main risk factors for the onset of insulin resistance, factors such as physical inactivity and poor dietary choices, that are wholly under our own control.
Our article this week is provided by Dr David Morris, who in the past few months has provided us with two blogs demonstrating how insulin resistance and Diabetes are clear examples of conditions that can be prevented and potentially reversed through a non-pharmaceutical and functional approach to treatment concentrating on dietary and lifestyle changes.
David’s most recent blog looked at Dietary Approaches to Reversing Insulin Resistance and this week he looks at the role of physical activity in potentially reversing insulin resistance.
Reversing Insulin Resistance – The Role of Physical Activity
Exercise is commonly promoted as a good way to lose weight but in isolation it is in fact extremely limited as an approach to weight loss – this is not surprising if we consider that, for the vast majority of us, in a 24 hour period we actually burn proportionally a far greater amount of calories while not exercising than we do while actually exercising.
For all their limitations, we can see from the so called calorie counters on exercise bikes etc. that the total amount of calories burned from a 20 minute fast jog is equivalent to one cookie! Hence the disgrace of Coca-Cola advertising their products alongside promoting exercise as if this counters the harmful effects of half a litre of carbonated treacle!
But I digress – there are in fact substantial benefits from exercising that are not simply about weight loss and it has been found to be an effective way to lower insulin resistance whether you are overweight or not.1
Why does exercise reduce insulin resistance?
If we cast our minds back to my previous post then we can remind ourselves that rising blood sugar leads to rising insulin leading to potentially chronically raised insulin and hence insulin resistance.
In simple terms exercise counters this by –
- Firstly, building muscle and therefore increasing glycogen storage so that more glucose can be taken out of the blood stream rapidly.
- Secondly, by using up glycogen stores. This of course happens directly while you are exercising but more importantly exercise boosts your overall metabolic rate so during exercise it goes up as much as 10 times more than at the resting rate AND the added advantage is that the metabolic rate will remain raised for up to 15 hours afterwards.
Some good news:
One of the points also discussed in my previous blog post was the implications of insulin resistance developing in muscles leading to poor glucose uptake and hence low cellular energy – not exactly ideal for setting off on an exercise regime.
The good news is that while glucose uptake into resting muscle cells is dependent on an effective insulin response this is not the case with exercising muscle – the muscular contraction itself opens up the receptors allowing glucose in over and above that entering via insulin effects.
How should you exercise?
This is quite a crunch question – if you have a physical job then in many ways the problem is resolved for you. But what of the rest of us with sedentary jobs and busy lifestyles? If you have the time (and motivation!) to intensively exercise 4-5 times per week for at least 30 minutes as per government guidance then fair play to you – BUT if this is difficult to achieve for whatever reasons then there is no need to give up and resign to the couch.
Take a walk after eating
Studies have confirmed that exercising after eating with diabetes is better at reducing glucose raising effects than exercising the same amount before eating. Simply taking a stroll after eating raises metabolic rate and reduce glucose and insulin surges.2
Grandma’s advice never to exercise on a full stomach does appear to be slightly flawed although intensive exercise will of course interfere with digestion.
Stand up regularly
Having a sedentary lifestyle (i.e. prolonged sitting), EVEN IF people meet the current recommendation of 30 minutes of physical activity on most days each week, leads to potentially significant adverse metabolic and health effects. This goes back to my earlier point that most people spend proportionally a far greater time relatively inactive even if they are exercising for 20-30 minutes per day.
Simply standing up and briefly moving is the key and it appears that the change in posture is the most powerful signal – not the act of standing up. This is important to understand because it means that the answer is to interrupt your sitting frequently not doing lots of standing ups in one go.
In other words standing up 30 times at once will provide only a small percent of the benefit of standing up once every 20 minutes –so set your timer and stand every 20 mins! The benefit is significant with weight reduction, lowered blood glucose and lowered inflammatory blood lipids all found simply by breaking up sedentary time.3
High Intensity Interval Training (HIIT)
HIIT is characterized by relatively short bursts of intense exercise with all-out, one hundred percent effort followed by short periods of rest/low exercise. For example running as fast as you can for 1 minute and then walking for 2 minutes or even fast walking then strolling i.e. whatever your current fitness level allows. As fitness improves clearly the intensity will go up.
This form of exercise actually matches our evolutionary history far more than most other forms of exercise – as hunter gatherers there is lots of low level activity and then sudden bursts of extreme exercise – either as predator or to avoid becoming prey!
Simply 10 minutes per day of HIIT 3 times per week has been shown to reduce insulin sensitivity, weight loss and visceral fat even compared to both controls and those performing “steady state” exercise.4
Why is HIIT so beneficial?
The steady state exercise group in the above study had a significant improvement in cardiovascular fitness alongside the HIIT group BUT did not see the same metabolic benefits. In other words your dedicated regular runner might not be as metabolically fit as someone using HIIT for a total of 30 minutes a week i.e. 10 minutes alternate days!
The reason for this is that the high intensity component uses “super-fast muscle fibres” which are 10 times faster than “slow fibres.” Activating super-fast fibres triggers Growth Hormone which is associated with longevity and a reduction in insulin resistance. Given that our levels of Growth Hormone start to fall once we are in our twenties then HIIT is an excellent way to reverse this.
A FINAL WORD (for now!)
It clearly makes sense to adopt a holistic approach to managing insulin resistance -after all we are complex systems not a linear system. Hence the next post will discuss stress and supplements.
In the meantime exercise and dietary should go hand in hand – unsurprisingly research has shown that they are more than the sum of their parts. In fact it has been demonstrated that aerobic exercise ONLY reduced insulin resistance if used in conjunction with carbohydrate restriction and not if only used in conjunction with calorie restriction.5
Dr Morris qualified as a doctor in 1994 and spent six years in hospital medicine – mostly in general adult medicine, but also in paediatrics and Accident and Emergency.
In 2000 David moved into family general practice and was a GP partner for many years. During this time he was also extensively involved in commissioning health care services.
Dr Morris has significant training and experience in complementary therapies such as acupuncture and homeopathy, and ran a primary care based pain clinic for over a decade using acupuncture therapies.
With many thanks to David for this article, if you have any questions regarding the health topics that have been raised please don’t hesitate to get in touch with me via phone (01684 310099) or e-mail ([email protected]).
Amanda Williams and the Cytoplan Editorial Team: Clare Daley, Joseph Forsyth and Simon Holdcroft
- N Engl J Med. 1991 Jul 18;325(3):147-52.Physical activity and reduced occurrence of non-insulin-dependent diabetes mellitus.Helmrich SP et al.
- Walking just after a meal seems to be more effective for weight loss than waiting for one hour to walk after a meal. Yasuyo Hijikata et al.
- Objectively Measured Light-Intensity Physical Activity Is Independently Associated With 2-h Plasma Glucose Genevieve N. Healy et al.
- The effects of high-intensity intermittent exercise training on fat loss and fasting insulin levels of young women. Trapp EG et al.
- Energy deficit after exercise augments lipid mobilization but does not contribute to the exercise-induced increase in insulin sensitivity. Newsom SA et al.