When we stop exercising deconditioning can set in as early as 2 weeks, however this depends on our pre-existing health status, training and fitness level and lifestyle. This means that when we start training again, we need to think of ourselves as starting from scratch.
What happens to your body if you stop training?
How does a return to exercise affect the musculoskeletal system?
During exercise, muscle fibres pull against one another, which is why your muscles often ache after exercise. Every time a fibre tears it repairs itself and grows back thicker and stronger, making more dense fibres. However, rest causes these fibres to weaken, which means that when we start exercising again post injury/rest it can lead to more micro tears in the muscle fibre, so it's crucial to start exercising slowly and gradually build it up.
Studies have shown that in the first week of 're-exercising', it's beneficial to have two days rest or to at least train on alternate days.
At this stage, your muscle pliability/flexibility will be low, which also increases your risk of injury. When you don't exercise, the synovial fluid (a fluid produced by the synovial membrane that surrounds the joint) reduces, which decreases the joint's range of motion and increases the risk of injury. A warm-up routine of gentle aerobic training and low-grade stretches will help to minimise this risk.
After 3-4 weeks, the muscles and connective tissue (ligaments and tendons) will start to get more elastic, so this is when you can start to think about increasing your training intensity.
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How does a return to exercise affect your cardiovascular system?
After 2-3 weeks of exercising, the blood supply to your musculoskeletal system increases as your muscles require more oxygen. Cardiovascular exercise increases the number of new blood vessels, while resistance (strength) training increases the size of these blood vessels (vasodilation). This is when the blood vessels expand to allow the blood to flow to your muscles more quickly.
So if you lose 15-20% of your cardio fitness you might find yourself struggling to breathe and suffer more fatigue, as the body won't be as efficient as it was at transporting oxygen around the body.
An increase in blood vessels means more efficient circulation, which lowers blood pressure (reducing strain on the heart); increases good HDL cholesterol that transports fat away from the arteries and back to the liver for processing; and reduces bad LDL cholesterol levels that can form fatty deposits in the arteries and contribute to heart disease. Blood vessels also bring much-needed nutrients to the muscles, which is why diet is important.
After 4-6 weeks of training, there will be an approximate 15-20% improvement in VO2 Max, i.e. the body’s ability to use oxygen. However cardio exercise, rather than strength training, is the best way to improve circulatory efficiency, as increasing the number of blood vessels is more beneficial than vasodilation.
How does exercise affect my heart?
How does a return to exercise improve your wellbeing?
Exercise produces endorphins throughout the body, which reduces anxiety, depression and improves self esteem. Exercise also leads to better quality and duration of sleep (deep sleep time), the importance of which cannot be stressed enough.
Deep sleep restores the body’s core functions, and improves your immunity and heart health. As we age, the part of our brain known as the hippocampus shrinks, impeding memory and general information retention. Exercising increases cell production in the hippocampus, which in turn makes us more alert and attentive.
Things to consider when you start exercising
* Start exercising again slowly, rather than going in at full training level. Around 30-40% of of your previous training intensity is a good starting point.
*Make sure you include a proper warm-up and cool-down.
* Avoid a complicated/intense workout programme during the first four weeks. For aerobic training, start with low-intensity endurance-based exercise, while for strength training increase the reps, rather than weight, during the first 2-3 weeks.
* Take your time and aim to regain your previous strength and cardio training level in approx. two months.
* Use this time to improve your technique.
* In case of inactivity due to injury, consult a physiotherapist/medical professional for a graded return.
Shelly Chakraborty is a chartered physiotherapist with Capital Physio
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