We do it all the time -- we eat something that makes us feel guilty (hey there, chocolate filled doughnut), and straight away we think, 'I"ll just go to the gym later to make up for it'.
Unfortunately, it doesn't work like that.
According to health experts, if you have an unhealthy diet, any exercise you do will not negate the food you eat.
"You really can't outrun a bad diet. Sure, you can exercise more to work off a few extra calories, however, you may be surprised at how much exercise is required to work off that extra glass of wine," nutritionist Fiona Tuck told The Huffington Post Australia.
How long does it take to work off junk food and alcohol?
- 40 minutes of intense weight lifting = 2 beers
- 20 minutes brisk walk = 1 glass of champagne
- 45 minutes brisk walk = 1 doughnut
- Three hour walk = Big Mac with fries
- Three hours of yoga = small barbecue pizza
Zoe Bingley-Pullin, a nutritionist and celebrity chef, agrees.
"You can't have one without the other. It's important to take a balanced approach to health by eating well and exercising often. Taking a one-sided approach is setting you up to fail and likely to burn out," Bingley-Pullin said.
If the focus is only on exercise, but our diet is filled with unhealthy processed foods, chances are we're missing out on vital vitamins and minerals obtained from whole foods like fruits, vegetables, whole grains, nuts and legumes.
"Exercise uses up energy (or kilojoules) so if you have a diet high in calories but void of nutrients, you are not giving your body the nourishment that it needs," Tuck said.
"Vigorous exercise such as running for hours can put the body under excessive stress, increasing the demand for nutrients such as magnesium, potassium, vitamin B and antioxidants. If you are exercising intensely but not nourishing your body with good food, you may be causing more harm than good."
Another mistake people often make when exercising more is decrease the amount of food they eat. This, again, does more harm than good.
"Imagine driving a sports car at full speed, not taking care of the car with regular services and putting in the poorest quality fuel and oil. It's going to wear out pretty quickly," Tuck said.
"Exercise is a stress on the body and we need nutrition to refuel and support recovery. If we undertake prolonged, excessive exercise without addressing nutrition we may develop nutrient deficiencies and burn out," Bingley-Pullin added.
"Food is the fuel we give to our body to exercise so an adequate diet will assist with exercise performance."
Look at food as nourishment for the body, rather than calories that can be burned off.
Of course, that's not to say we should never exercise. Exercise is important, too.
"Exercise is crucial to maintaining our health and mental wellbeing. Exercise helps produce endorphins, lowers blood pressure and blood sugar, helps to maintain a healthy body weight, balances hormones, and increases bone and muscles mass," Tuck said.
"The more muscle mass we have the higher our metabolic rate (meaning we need more food). If we exercise without providing adequate nourishment to the body we are basically causing more wear and tear in the body and accelerating the ageing process."
Once a healthy diet and exercise go hand-in-hand, you can expect to feel healthy, both inside and out.
"Food and nutrition are the foundations of health. Specifically, our food is the building blocks for cell growth and development and gene expression. All of which goes on to impact mood, energy and overall wellbeing," Tuck explained.
"A shortage of nutrients from a poor diet will go on to impact the running of our bodily processes and ultimately the way we look and feel."
Many people get confused with eating and exercise for health and wellbeing, and eating and exercising to look good.
So, what's the magic rule? Is it 50/50 diet and exercise, or the popular 80/20 rule?
"When it comes to maintaining a healthy weight, a general rule is 80 percent comes down to the food we eat and 20 percent comes down to how much we exercise," Tuck said.
"Exercise alone will not provide the body it needs for healthy biochemical reactions to occur. If anything, intense exercise increases the demand for a higher nutrient intake. What we put into our mouths on a daily basis really is very important."
According to nutritionist Christine Cronau, the ratio of diet to exercise should be even higher.
"I would go so far as to say that it is closer to 95 percent and 5 percent. Of course, exercise is very beneficial for growing muscle and toning, but the effort won't show if we are storing extra fat," Cronau told HuffPost Australia.
Bingley-Pullin said it's also important for the exercise ratio to also include daily movement, such as getting up from your work desk and going for a walk.
"Prolonged sitting is linked to increased risk of disease, so in addition to structured exercise, it's important to move regularly throughout the day," Bingley-Pullin said.
Want to implement the 80/20 rule but don't know where to start? Try these three simple tips.
1. Start with small changes
If you're not used to eating a healthy, varied diet, Bingley-Pullin recommends making small changes to your usual meals.
"If you don't yet have the balance, start making small gradual changes such as eating a healthy breakfast, adding a serve of vegetables to dinner and making sure you drink enough water when exercising," Bingley-Pullin said.
"Change won't happen over night but every little bit counts."
2. Focus on how you feel, not how you look
Being healthy isn't about having a 'fitspo' body. While it is tempting, focus on the differences you feel (for example, having more energy, being stronger, feeling happier, sleeping better, etc.), rather than how you look in the mirror.
"Many people get confused with eating and exercise for health and wellbeing, and eating and exercising to look good," Tuck said.
"We can exercise daily and eat very little and we may look good on the outside, but our bodies may be suffering on the inside."
3. Look at food as nourishment
Instead of seeing food as 'the thing that makes me fat', see it as a way to help you function optimally and exercise. Food is simply fuel, and healthy food can be delicious.
"Look at food as nourishment for the body, rather than calories that can be burned off," Tuck said.
"Every single thing that we put into our mouths has the ability to harm or heal our bodies. Treat your body with care and nourishment, rather than gruelling, punishing exercise regimes to burn calories."
For information about eating disorders, contact the Butterfly Foundation on 1800 33 4673 or talk to your GP, local health professional or someone you trust.
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