Whether you want to build muscle or increase aerobic endurance, everyone is looking for results. If you’re curious about how your body responds to exercise (and how long it takes to see changes), accredited exercise physiologist Harry Beresford dives into this topic below.
Just remember that to get results, you need to move regularly. This means doing at least 30 minutes of physical activity on most days of the week. If you can’t, then try to be as physically active as you can in your current state of health. Any movement is good and something is always better than nothing.
Heart rate – changes within a couple of weeks
The heart is a muscle, and as you get fitter, it will become stronger. This leads to an increased stroke volume, which means your heart will pump more blood per beat than before. This can, in turn, decrease your resting heart rate.
Resting heart rate can decrease by up to 1 beat/min in sedentary individuals with each week of aerobic training, at least for a few weeks. Other studies have shown smaller reductions with fewer than 5 beats following up to 20 weeks of aerobic training.
Your maximum heart rate typically stays unchanged with regular training and is more likely to decrease over time as part of the normal ageing process.
People who are fitter also tend to have a heart rate that recovers faster after exercise.
Blood pressure – changes in a few weeks
Exercise causes modest reductions in blood pressure in those who have borderline or moderate levels of high blood pressure. The average reduction in systolic and diastolic blood pressure for those who have high blood pressure and perform regular aerobic activity is 7 and 6 mmHg respectively.
One study showed that simply increasing your step count can lead to a reduction in systolic blood pressure of ~4 mmHg. This may seem small, but a 5 mmHg drop can reduce the chance of death by stroke by 14 per cent.
Individuals with blood pressure in a ‘normal’ range experience little long-term change in their BP at rest or with exercise.
Aerobic Fitness (aka VO2max) – changes in a month or two
VO2max, which is the highest rate of oxygen consumption possible during maximal or exhaustive exercise, is a great indicator of someone’s physical fitness. With endurance training, our body can deliver more oxygen to the working muscles allowing it to do more for longer and with reduced effort.
Improvements range from 5-30 per cent with a regular, sustained program. Untrained individuals can see improvements of 15-20 per cent in their VO2 max following a 20-week aerobic training program. This allows them to perform an activity (e.g. running) at a higher intensity.
Muscle fitness – expect to see small changes in the first few months
Within three to six months, an individual can see a 25-100 per cent improvement in their muscular fitness – provided a regular resistance program is followed.
Most of the early gains in strength are the result of the neuromuscular connections learning how to produce movement, sometimes accounting for up to 50 per cent of strength improvements in the early stages of a strength-based program.
Changes in muscle size from resistance training are highly variable, from no change at all up to roughly 60 per cent increases with a long-term resistance program.
Weight loss – results in a few months
Exercise can be used as an effective tool for weight loss and also preventing weight gain. People wanting to lose weight should aim to be physically active for at least 30 to 60+ minutes per day to notice any significant changes. It also needs to be at a moderate intensity.
One study with 52 obese males reported a body weight decrease of 7.5kg over 3 months using only exercise. Participants did ~60 minutes of exercise per day with a goal of 700 calories (~2940kJ) expended.
Another study with 52 overweight males and females reported a weight loss of 7 per cent over 16.8 weeks with exercise alone. The amount of activity completed was 7.4 (+/- 0.5) hours per week.
However, it’s important to note that exercising alone to lose weight is not sustainable in the long term, as eventually your body will become accustomed to the new amount of exercise you’re doing, and your metabolism will adjust to this. Therefore, your diet is even more important than your physical activity for weight loss.
The studies mentioned above focused on people with a high amount of excess fat who previously had done little amounts of exercise. So, if you do not have a high amount of excess fat and you already do plenty of regular physical activity, upping your amount of exercise to lose weight is likely to not work very well for you. It can also result in burnout and injury when not done in conjunction with a health professional, so it’s best to seek advice from a qualified expert or your GP before engaging in exercise to lose weight.
Find out more about why losing weight is an ineffective motivation to exercise.
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Mental health – changes in as little as 10 minutes!
While there are numerous physical benefits from regular physical activity, it benefits our psychological health, too. Even brief walks, at a low intensity, can improve our mood and energy levels. You can start to notice positive effects after as little as 10 minutes of aerobic training.
Things to remember
- It’s important to focus on enjoying the physical activity you do. Exercise isn’t just a way to lose weight or reduce high blood pressure. We call this your intrinsic motivation.
- Try to look at physical activity as a lifelong journey rather than a short-term project. For example, think about how weight loss will improve your long-term health, rather than just help you fit into those jeans.
- Find something that you’re excited by and motivated to do. That might be social netball or a class at your local gym. If you’re looking forward to it, then there’s a greater chance you will stick to it over the long term.
- Make a plan – not sure how – read more here.
- Get friends and family involved – it’ll help you to achieve your goals, make it more fun and keep you accountable.
If you’re still curious about the many benefits of regular physical activity or you’re struggling with the motivation to stay active, chat to your local Accredited Exercise Physiologist.
This article was written by Harry Beresford, ESSA Accredited Exercise Physiologist. It’s republished here with permission from Exercise Right. Read the original article.
Main image: Adobe Stock
