Posted by Dr Robert Buist in Weight Loss posted:

Exercise vs Diet

On our Wheyless shows we often talk about the relative benefits of exercise versus diet for weight loss, with emphasis placed primarily on the importance of the dietary aspects. And as it turns out, many researchers agree.

Dr Shawn Talbott, for example, a nutritional biochemist and former director of the University of Utah Nutrition Clinic, has found that weight loss is generally influenced by 75% diet and 25% exercise. People who dieted without exercising for 15 weeks lost 10.4 kg on average while those who only exercised lost just 2.7kg over 21 weeks. You need to workout quite hard to burn calories. In fact, you would need to run 6km to undo the effect of eating just 500cals.(1) 

There are about 500cals in a normal cheeseburger.(2) So, you can see the problem with trying to lose weight using exercise alone, especially if your overall diet leaves you with unused, excess calories at the end of the day. 

Does this mean we shouldn’t worry too much about exercise though? No, it doesn’t and quite contrary in fact. Exercise, especially aerobic exercise, has a great deal to offer.

Exercise floods our body with oxygen. It enhances the production of new blood vessels, which supply more oxygen to the mitochondria. Most of our energy is produced in the mitochondrial powerhouses found in our muscle cells. The more oxygen that we can supply to our muscles, the more energy we can produce. Keeping our mitochondria more effective also slows the aging process.(3,4)

Regular exercise improves sleep, boosts the immune system, heightens cognitive abilities and helps increase lifespan. 

Researchers found that high-intensity biking reversed the ageing process. Younger volunteers showed a 49% increase in mitochondrial capacity while an older group demonstrated a huge 69% increase rather than an expected age-related decline in mitochondrial function. They also found an improvement in participants’ insulin sensitivity, thus lowering the risk of developing diabetes.(5)

So, when we say that diet and nutrition are the backbone of any weight loss regime, exercise should not be overlooked. A healthy oxygenated metabolism will benefit any weight loss program, and this appears to be increasingly true as we age.



  1. Wexler SZ. Exercise vs. diet: the truth about weight loss. Huffpost 2014 [online]. Viewed 20 Mar 2019,
  2. Forwood SE, Ahern A, Jollands GJ, et al. Underestimating calorie content when healthy foods are present: an averaging effect or a reference-dependent anchoring effect? PLoS One 2013;8(8):e71475.
  3. Nicastro R, Mitochondrial Adaptations to Aerobic Training. International Sports Sciences Association 2018 [online]. Viewed 20 Mar 2019,
  4. Sun N, Youle RJ, Finkel T. The mitochondrial basis of aging. Mol Cell 2016;61(5):654-666.
  5. Newman T. Exercise prevents cellular aging by boosting mitochondria. Medical News Today 2017 [online]. Viewed  20 Mar 2019,


Dr Robert Buist

Wheyless Formulator

Wheyless was formulated for Fit-BioCeuticals Limited by Nutritional Biochemist Dr Robert Buist PhD.

Dr Buist has a degree in Biochemistry from the University of NSW and a PhD in Medicinal Chemistry and Pharmacology from Macquarie University in Sydney. He is one of Australia's leading experts in weight loss.