How do we get fitter?


Well, I’ve got news for you… a huge percentage of the people who took part on the day were like you, they once thought, just like you that they couldn’t run for a bus let alone a finishers medal. But, something inspired them, weather it was to raise money or they’d been through a traumatic experience or they simply wanted to set themselves a goal, they did it and do you know what? so could you!

OK, you might not fancy 26.2 miles but you can become active and increase your physical fitness. The reason is your body is amazing, ‘why, thank you’ I hear you say- no, not like that (although it might be!) It’s amazing because it adapts. Slowly over a matter of weeks physiological changes take place that we’re not even aware are happening to us.

Have you already experienced an improvement in your fitness? In the early days you may have staggered out of the pool/ studio/ gym/ local park, your face an impressive glowing red; your heart beating so hard it can clearly be seen thumping against your sweat soaked skin, your lungs singing like a set of bag pipes and your legs barely able to hold you up. But, over the weeks you start to notice that you’re not as red, your heart rate settles back to normal more quickly, your lungs are no longer singing and actually, your legs are looking pretty good???

Most of us understand that the heart and lungs or cardio-vascular system are involved in this getting fit malarkey but what actually happens to them?

The Heart

If our heart regularly beats faster for at least 20- 30 minutes a day it will eventually adapt and become more efficient at pumping blood around our bodies to muscles which need extra oxygen and nutrients to be able to allow us to be active.


The heart is a muscle and just like any muscle it responds well to exercise. An average heart beats between 60 and 80 beats per minute, a heart that is used to regular physical activity will become bigger, particularly the left ventricle which is the main pump. The increase in size means that the heart contracts stronger, pushing a greater amount of blood around the body each contraction and each minute. This results in the muscles receiving what they need so that they build up endurance. A trained heart will have a lower resting rate which is an indicator that the heart is become fitter!

The Lungs

When we exercise, the brain has a word with your diaphragm and rib muscles to work harder. Your diaphragm contracts and allows the lungs to expand. The lungs don’t get bigger in size when you become fitter but the capacity will increase and they will become more efficient at taking in oxygen and getting rid of waste products. You’ll notice that your breathing rate will increase until the muscles surrounding the lungs can’t physically do any more work, this is measured as the maximum capacity of oxygen we can use otherwise known as the VO2 Max.

The circulatory system.

When we exercise the blood flows less to our major organs but more to the working muscles. At rest 20% of the blood flow goes to muscle compared to 88% when we are active. To cope with this we increase the amount of capillaries in our body, these are the smallest of our blood vessels. The increase of capillaries means that blood is infused into muscles easier and waste products are taken away to our lungs to be exhaled out of the body more efficiently.


Our muscles respond to exercise in several ways. Muscle cells contain little power houses called Mitochondria. These little beauties contribute to the amount of work our muscles can do. As we get fitter and over-load the muscles we develop more mitochondria. They also get bigger in size so that our muscles have more energy and work for longer.


The part of exercise that people usually loathe is the soreness afterwards. This is known in the trade as Delayed Onset Muscle Soreness or DOMs, typically occurring 12-72 hours after exercise. It’s nothing to worry about; it’s our bodys normal response to exertion. Unless you are really in severe pain and there is localised swelling it is unlikely that you have seriously damaged yourself! A sedentary person who decided to knock out a fair few sit-ups complained to me a couple of days later that they were in agony and suspected that they had appendicitis, when I asked what they’d been doing I was able to assure them that they were not in any imminent danger of having their innocent appendix whipped out and that the pain would settle down.

Why does it hurt?

When we exercise we create teeny weeny tears on the muscles, the muscles responds to this by growing bigger and stronger. This doesn’t just happen to people who are new to exercise, it will happen if you do a different activity that you’re not used to or you add extra intensity.

Howe long does all this this take to happen?

How many times have you started exercise and given up because after one week you’ve not noticed a difference? How many times have you agreed with yourself that exercise just isn’t happening for you and you give up? These physiological changes take time to happen; I know we all want everything NOW but this can’t be hurried. Obviously, the more you do the quicker these changes take place so if you are physically active three to five times a week your body will adapt much quicker than if you only do something once a week. All these changes are reversible, if you stop being active the body adapts back to it’s pre exercise state again…just warning you!!

Our bodies are truly amazing (yes, even yours!) and believe it or not, we are designed to move not to sit on our bum! Take it slowly, build up gradually, and increase your speed and intensity regularly for cardio vascular fitness. Walk at a brisk pace and break into a light jog when feel ready. Walk for two minutes, jog for one, change this to walk for one minute and jog for two and before you know it, you’ll be jogging for ten! Start with light weights and do two sets of 12-15 repetitions and gradually increase the weights that you use and decrease the reps. Your fitness Instructor will be able to advice you and provide you with a programme.

Help is here!

Or, if you really need something to inspire you, on Sunday 10th July Cancer research race for life is in Stevenage.SLL have been asked to support this event and promote the 10k distance run. What better way to improve your fitness and support a very worthwhile charity at the same time!

Look out for some daily blogs to help you get the best from your training for this event. Sorry lads, this event is ladies only but you can still follow the training tips…

We have a Stevenage Lifestyles team if you would like to be part of a group for extra motivation. Don’t forget, you can walk, jog or run this event Go to  – and find the Stevenage 10k event. When filling in the details it says join or create a team – Put in our team I.D – FC9086 and that will put you in Team Stevenage Lifestyles!

So, the next time you put that onesie on could be as fancy dress when you take part in the local fun run!

Go on you amazing person, get out there and go for it!

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