Saturday Morning Research Review – April 16, 2016

Exercise science update: 8 exercises for overall strength and 1 method to limit running injuries

by Adam Burrack, PhD

Our mission at YOUglycemia is to promote improved diabetes management through education and empowerment. We see it as a significant part of our mission to promote aerobic exercise due to the clear benefits in insulin sensitivity, self-efficacy, and mood enhancement.

An important caveat with aerobic exercise is that muscle strength, power, and flexibility are all important aspects of overall fitness as well. Without specific workouts aimed at improving these aspects of fitness, aerobic-focused athletes run the risk of becoming “one-dimensional”, including developing strength imbalances (for runners, for example, quad strength at the expense of hamstring – or biceps femoris – strength and flexibility). Over time, these imbalances can lead to over-use injuries, putting us “on the shelf” (or on the sidelines) and impairing athletic performance.

As diabetic athletes we are all well aware that going onto the shelf with an unplanned injury is a recipe for turning our diabetes management upside-down. In other words: exercise as a tool for diabetes management is most useful when it is consistent and sustainable. A key component of a sustainable exercise program is to work on ancillary skills including total-body strength and flexibility, not just aerobic endurance.

A recent article in Runner’s World describes 8 tests of overall fitness, none of which involved long-distance running. Given the recent trends of P90X, Tough Mudder events, and CrossFit, the theme of this article was not surprising. What was interesting to me was that this article was published in Runner’s World, specifically for distance runners – who are perhaps the most notorious “one-dimensional” athletes of all. For anyone who remembers the “Presidential Fitness Test” from elementary school, these will look very familiar.

The tests evaluate the following categories (1) core strength – holding a plank, (2) lower body power – standing broad jump, (3) anaerobic endurance, (4) mobility, (5) cardiovascular endurance (“the beep test” or shuttle run), (6) upper body power – clapping push-up, (7) the go-muscle test – deadlift 1.75 times your body weight, (8) flexibility – specifically in the hamstrings. For my own personal project of racing the track mile this winter and summer, the power and strength aspects of these exercises will be key. I have some work to do in those categories.

Related to overall fitness and athleticism, a recent New York Times article described a recent study in which British researchers attempted to determine how some long-distance runners avoid injury – for years. Any long-time runner will be aware that injuries are a part of the game. To become an “old runner” (my personal definition: anyone who has remained competitive at distances from the mile to the marathon for >10 years post-college), one has to make peace with one’s limitations. One of those limitations is the weekly running mileage above which we are more prone to injury – as well as the types of workouts from which we are most likely to become injured. There are times when the entire “game” with long-distance running seems to be avoiding injuries and staying consistent. It’s a truism in elite marathon running that the current best performers are almost always in the middle of a long stretch of injury-free training. Add to this my comments above the entire point of exercise with type 1 diabetes is to enhance our diabetes management through consistency of exercise, not to have a great 6 months and then take the next 2 years off due to injury or burn-out. Taking long breaks from exercise returns us to baseline fitness, whereas consistent training over years – with short breaks several times per year – facilitates continued improvement over time. This improvement includes enhanced mitochondrial density, enhanced insulin sensitivity, and improved body composition. None of these changes happen overnight, but all of them can be a boon to diabetes management.

Through this prism, a recent British study of running biomechanics made an important observation. The authors used force plates on a track to measure the literal force with which each runner in a group of several hundred hit the ground with. Then they tracked frequency and severity of running-related injuries over the next several years. The least frequently injured runners ‘hit the ground’ with the lowest forces in their study. In other words, the “most beautiful” runners (ie. those with the biomechanical ‘best strides’ and lower ground forces), were also those who were least frequently and least severely injured. This does not necessarily mean they were the fastest runners. Indeed, being the most competitive runner is not the point (at least not for me, my VO2 max is not 85, its 65!), the point is staying consistent through avoiding injury. We can avoid injury through improved biomechanics. One other important finding: runners who landed on their heels could be just as light on their feet as runners who land on their mid-foot. So it’s no good trying to force yourself to run on your toes: that does not appear to be a short-cut that will accomplish the goal of improved running form. This study suggests that activities which train runners to be lighter on their feet – to literally be more athletic – like the 8 exercises to test overall fitness, above, can have far-reaching benefit for their health and well-being through facilitating consistent exercise habits.

Along this line, there is one more reference on running biomechanics I would like to call our readers’ attention to a recent book by Master’s runner Pete Magill and colleagues titled, “Build Your Running Body”. This book contains examples and explanations of a range of running-related strength and conditioning exercises that should form an important component of well-rounded athlete’s training. Performing these types of total-body exercises is an important part of my exercise routine, one which I hope will help prevent running-related injuries. While the strength and flexibility work may not be the reason I exercise, these disciplines are key for my ability to keep exercising for enhanced diabetes management.

Posted in Exercise, Research Review, Running, Training.