Stepping into the New Year – by Dr Alex Ryan
Happy New Year! And with that it’s time to make your resolutions. After overindulging over the holidays, it’ll come as no surprise that a lot of people choose to start getting healthy, by eating better and exercising more. We’ve covered food last month, so I’m going to focus on the exercise in this blog.
Everyone knows exercise is good for you. It has numerous health benefits from preventing heart disease, stroke, osteoporosis and several cancers, improving depression, and crucially for those with Type 2 Diabetes it can improve insulin sensitivity in muscles. Skeletal muscle (the stereotypical muscles involved in exercise) is cumulatively the largest organ in the body, and accounts for 90% of sugar uptake after a meal. Obesity and a sedentary lifestyle are linked to the onset of Type 2 diabetes, and increasing exercise can drastically improve glucose uptake and insulin responsiveness.
So how does it work? In skeletal muscle, and fat, insulin causes a specific channel called GLUT4 (it stands for glucose transporter 4) to the membranes of cells. This means that sugar can enter the muscle. In insulin resistance and Type 2 diabetes this process doesn’t happen properly. During exercise GLUT4 also moves to the membrane, but through a different way to how insulin makes it move. Exercise also increases the amount of GLUT4 available.
As well as improving the muscle directly, exercise has other beneficial effects. Part of my work, and others, has shown that during exercise the muscle begins to release molecules called myokines. These myokines can move throughout the body and have positive effects on other organs, especially those beneficial to Type 2 diabetes like fat, the liver and the pancreas.
Obesity and a sedentary lifestyle are linked to the onset of Type 2 diabetes, and even a small amount of exercise can help. As anyone who struggled through a gym initiation will tell you, the prospect of exercise can be a daunting one. Recently, an article stated that a five-minute walk for every three hours sitting can improve the circulatory system, but is that enough for improving Type 2 diabetes?
The first thing I would suggest is getting a pedometer; it’s a little machine that counts your steps. You can download an app on most smartphones for free, so there’s no excuse really, and it has been shown that those with pedometers exercise more than those without.
Around 5,000 steps a day can be considered low active, without any other exercise. Whilst that seems like a lot it, only works out to less than 2.5 miles; about a hour’s slow walking. Most people walk 5,000-7,500 steps every day, but of course the more steps the better, and it is recommended that people aim for around 10,000 steps a day. A recent study showed that encouraging those with Type 2 diabetes to walk 10,000 steps a day significantly improved their quality of life.
Last year a study suggested going for a 15-20 minute walk after eating. This is an easy way to chalk up a second 5,000 steps, and furthermore the increased GLUT4 availability helps the muscle take up sugar after a meal. As the muscle is the main depository for sugar this uptake is important. Interestingly, this study showed that these numerous small walks are actually more beneficial to glycaemic control than a relatively long 45-minute walk. As well as these benefits, people carrying out multiple short exercises are more likely to adhere to an exercise plan.
So, there you have it. If you’re looking for a simple way to start exercising, short walks can definitely be recommended, and are an excellent way to kick off 2015.