Stronger, Fitter, Happier

Stronger, Fitter, Happier teaser image
It sounds a bit like the sequel to Daft Punk’s “Harder, Better, Faster, Stronger”. Perhaps those French robots were onto something!

There is something to it though. It’s no coincidence that the people you see that are strong and fit, are often the same ones with a content smile on their face (except perhaps during a gruelling event). Exercise has long-been associated with good mental health (1). In fact, people who exercise have over 40% less ‘poor mental health’ days than those that don’t exercise at all (2).

But how does it work? And what sort of exercise is best? Here we talk through some of the science and implications of how physiological changes that occur during exercise impact mood and ‘good feelings’.

The science behind exercise and mood

Exercise is arguably our best regulator of all major systems in the body, be it musculoskeletal, metabolic, cardiorespiratory, immune, or our nervous system. Mood is essentially an output of the brain – part of your nervous system - and your nervous system is regulated by changes in certain chemicals around your body.

When we exercise, we release dozens of endorphins (anti-stress hormones) which have different effects on the brain (3). These, along with dopamine, serotonin, and oxytocin, are often affectionately known as “happy hormones”. Here’s how they work:

- Norepinephrine wakes up the brain and gets it going,
- Dopamine, associated with anticipation of pleasure, gets a boost and helps to improve your mood and motivation
- Serotonin affects the limbic system and how we perceive and regulate emotions.
- BDNF (brain-derived neurotropic factor) generates and protects our brains nerve cells against cortisol

Cortisol (stress hormone) actually increases during activity, but then reduces later. Think of this effect like your heart rate. Yes – it increases during exercise, but the more bouts of activity you do, the more efficient the system becomes, and the less “beats” (or cortisol) you produce at rest.

Exercise, as opposed to incidental physical activity, also provides some wide ranging social and psychological benefits. It can facilitate better social interactions, sense of worth, achievement and routine, all of which can play a big role in mental wellbeing (4).

What exercise is best?

Exercise, like people, can come in all shapes and forms. Huff and puff activities, such as running, cycling, swimming and some team sports, fall broadly under the banner of aerobic exercise. This simply means that these activities require high levels of oxygen intake (5). If you feel like your breathing hard, fair chance you could say you’re doing aerobic exercise.

Resistance (strength) training is another broad category of exercise. This includes things like weight-lifting, pilates, resistance band and body-weight exercises such as, you guessed it…PUSH-UPS.

Both aerobic and resistance exercise are well established in research as having high associations with good mental health(2, 6, 7).

Some exercise types don’t fall quite as easily into these categories, but can still have significant positive impacts on your mental health. Yoga and tai chi, for example, might not get your lungs bursting or your muscles burning, but employ great mindfulness techniques which highlight the psychological benefits of exercise.

How much is enough? Some is better than none, and more is better than some. If you want to optimise your approach and aim for that ‘sweet spot’, Australia’s national physical activity guidelines suggest adults (8):

• Aim to accumulate 150 to 300 minutes (2 ½ to 5 hours) of moderate intensity physical activity OR 75 to 150 minutes (1 ¼ to 2 ½ hours) of vigorous intensity physical activity, or an equivalent combination of both, each week
• Do muscle strengthening activities on at least 2 days each week.
• Be active on most, preferably all, days every week
• Doing any physical activity is better than doing none. If you currently do no physical activity, start by doing some, and gradually build up to the recommended amount

Other tips from an Exercise Physiologist:

1. Do something you enjoy. This may be the biggest factor in your ability to get going and keep going. Don’t really enjoy any exercise? Then try something you can at least tolerate :)

2. Start small and build up. This is already part of the national guidelines, but is important to reiterate. In fact, people who get the biggest bang for buck in exercise-related health benefits, are those that go from doing nothing to doing a little.

3. Plan and diarise your exercise schedule. The best exercise is the one that’s done, so try and create a routine that you can keep to. It’s also helpful to have a ‘plan B’, for the days or weeks that life just gets in the way.

4. Consider exercising with friends, family or peers. Exercising in groups can help keep you motivated and accountable. Good banter can also keep the smile on your dial.

5. Set goals, if it helps. If you struggle with motivation, goal setting can be really helpful to keep you on track. Whether that be building to daily exercise, training for a fun-run, or say, a certain number of push-ups in 3 weeks, setting a goal can keep you motivated. When you accomplish something, you also get a little dopamine hit that gives you that sense of pleasure and fulfilment.

6. Consider seeing an exercise professional. If you’re struggling getting started, progress, or have other health-related concerns, an appropriate exercise professional can help tailor a routine that’s appropriate for you, suit your goals, ability and lifestyle.

Author: Jonny Christie, Director & Exercise Physiologist at Agility Rehabilitation

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8. Brown WJ, Bauman AE, Bull FC, Burton NW. Development of Evidence-based Physical Activity Recommendations for Adults (18-64 years). Report prepared for the Australian Government Department of Health, August 2012