The importance of cross training and building strong bones

photo featured in the Daily Cycle Flickr Group – added by sharonnord

I am a keen runner and a cyclist and I try to do as much of both as possible. It often leaves me wondering, however, whether doing one complements the other or not. Obviously, any form of aerobic exercise is going to help overall fitness and running is a brilliant way to build fitness with relatively short workouts. Unfortunately, the truth is that running and cycling use muscles in completely different ways and therefore it is unlikely that the two have any beneficial training effect on each other.

Pedalling shortens your muscles

The reason is that cycling causes muscles to shorten when they contract (also known as a concentric contraction) whereas running causes your muscles to elongate when they contract (also known as an eccentric contraction). If you think about the way your legs move on the bike it is easy to see how the movements are controlled by muscles shortening; as the relative muscle is working, the angle of the joint that it affects becomes smaller e.g. hamstrings flexing the knee. Here is a nice little diagram indicating the muscles that are used during each stage of a pedalling revolution:

Now this may explain why, when you go out to play football with your kids, the next day your legs are killing you! The motion of running elongates the muscles that you have been shortening every time you go on the bike. I have highlighted the importance of stretching in one of my previous articles and chances are that if you stretch properly and keep your muscles supple, that you won’t feel as sore the day after running than someone who doesn’t stretch.

Don’t neglect your upper body

Now let’s have a look at swimming. I personally am a rubbish swimmer which is quite frustrating as I would love to compete in triathlons! Again, swimming is brilliant for building up aerobic fitness and helps to build strength in all the major muscle groups of the body. The quadriceps, hamstrings and gluteal muscles all get a good workout while swimming, however I think the most beneficial thing about swimming is that it works the muscles that you don’t usually use when cycling.

It is easy for cyclists to neglect their upper body, abdominal and back muscles. Now, if you’re a really serious cyclist then this might be because you don’t want any unnecessary additional weight to carry up hills but let’s face it, most of us carry a little bit of additional weight anyway!

Keeping your upper half in good shape is essential to overall health as it is the back and abdominal muscles that support your spine and help maintain good posture. Now which cyclist is going to argue that maintaining good posture isn’t important when you’ve been hunched over a bike for 3 hours a day! Cyclists often get neck and back pain from being in this unnatural position for long periods of time and therefore swimming is a great way to take time to look after your whole body.

Overall, in my opinion, cross training really is essential to maintaining good health and reducing the risk of injury. Keeping core and back muscles strong help to support your spine and limit the effects of unnatural positioning on the bike. The more you cross train and use your muscles in a variety of ways, the more easily they will adapt every time you do something different. The body is an amazing piece of machinery and every time you go for a walk or a bike ride your bones and muscles are making themselves stronger and adapting so that they can perform better next time.

Exercise strengthens bones

I think it’s important to mention that it is exercise that helps to build strong bones. The impact of your foot on the ground and the pulling and tugging of tendons and muscles create micro-damage to the bones themselves which is then repaired and the bone becomes thicker and stronger. It is thick strong bones that help prevent things like osteoporosis developing later in life.

For women especially, exercising in their reproductive years is absolutely vital. It is estrogen that allows the process of bone breakdown and repair to happen in women and once the menopause is over, it is no longer present in their bodies. No estrogen means that the bones can’t repair themselves; they become thinner and thinner as the micro-damage cannot be repaired.

Eventually this can lead to osteoporosis which kills more women than all cervical and ovarian cancers put together. If an elderly lady with osteoporosis falls and breaks a limb, the bone disintegrates like dust and there is no way of repairing it – even surgically. She will become immobile and eventually all the physiological processes in her body will give up on her and she will die. There is hardly any awareness of the severity of osteoporosis, yet it is so common. So ladies get exercising and make those bones as thick as possible to stand you in good stead for the rest of your life.

Happy cycling :-)

Image credit:

1. http://cozybeehive.blogspot.com/2006/10/what-muscles-are-you-using-to-pedal.html
2. http://www.beliefnet.com/healthandhealing/getcontent.aspx?cid=%09%09%09%09%09%0911641