Dylan Thompson
drdylanthompson.bsky.social
Dylan Thompson
@drdylanthompson.bsky.social
Professor at the University of Bath, UK
https://researchportal.bath.ac.uk/en/persons/dylan-thompson. Co-Director of the Centre for Nutrition, Exercise and Metabolism https://www.bath.ac.uk/research-centres/centre-for-nutrition-exercise-and-metabolism/
Collectively, there seems to be a double benefit from exercise - a transient increase in key vitamin D metabolites around each bout (shown in our previous acute exercise RCT below), and longer term sustained positive effects on basal concentrations.
physoc.onlinelibrary.wiley.com/doi/full/10....
The effect of an acute bout of exercise on circulating vitamin D metabolite concentrations: a randomised crossover study in healthy adults
Abstract figure legend Thirty-three healthy adults (14 ♀, 41 (15) years, body mass index 26.2 (3.7) kg/m2, V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ 36.2 (9.2) ml/kg/min; mea...
physoc.onlinelibrary.wiley.com
May 12, 2025 at 7:25 PM
We previously speculated that exercise might mobilise vitamin D from adipose tissue. Adipose can contain enormous amounts of vitamin D. This didn’t seem to happen but, as we discuss in the paper, interpretation is complex and there is a lot to consider. onlinelibrary.wiley.com/doi/full/10....
Mobilising vitamin D from adipose tissue: The potential impact of exercise
Vitamin D is lipophilic and accumulates substantially in adipose tissue. Even without supplementation, the amount of vitamin D in the adipose of a typical adult is equivalent to several months of the....
onlinelibrary.wiley.com
May 12, 2025 at 7:25 PM
The preservation of active vitamin D (1,25(OH)₂D₃) is particularly notable given that supplementation doesn’t seem to have such an effect. Our take home if you don’t want to read on - Exercise should be promoted alongside supplementation to help maintain vitamin D status
May 12, 2025 at 7:25 PM
This is patently not true. The two robust RCTs providing causal evidence (which we refer to in this piece) were funded by the US National Institutes of Health - not industry.

The public deserves better.
January 30, 2025 at 3:57 PM
And, they are ignoring the strongest evidence. We now even have celebrity doctors claiming that “the whole idea that you can burn more calories by doing exercise was funded, if not by Coca Cola, then by the soft drinks industry”

www.youtube.com/watch?v=j1oO...
Ultra processed foods and the third age of eating - with Chris van Tulleken
YouTube video by The Royal Institution
www.youtube.com
January 30, 2025 at 3:57 PM
Is it the science - and the intriguing notion that physiological systems have evolved which conspire against our efforts to make changes that would be positive in modern-day environments?

Whatever the motivation - they have got carried away!
January 30, 2025 at 3:57 PM
Is it knowing that many of the general public will enjoy articles allowing them to scoff at the futile behaviour of people who might otherwise appear virtuous (exercisers)?
January 30, 2025 at 3:57 PM
Why do journalists find the constrained energy expenditure narrative so enthralling? Is it because it gives the impression we have all been duped?
January 30, 2025 at 3:57 PM
That’s not to say that there might not be some interesting interactions as we discuss in this paper. pubmed.ncbi.nlm.nih.gov/36828336/
I just think we need to be careful not to throw away the baby with the bath water!
Perspective: Is the Response of Human Energy Expenditure to Increased Physical Activity Additive or Constrained? - PubMed
The idea that increasing physical activity directly adds to TEE in humans (additive model) has been challenged by the energy constrained hypothesis (constrained model). This model proposes that increa...
pubmed.ncbi.nlm.nih.gov
November 27, 2024 at 7:45 PM
The constrained model is certainly interesting, but I don’t think we are ready to say that people who are really active burn the same as people who are really sedentary. Indeed, during the RAUSA experiment, the athletes burned >5,000 kcal/day - not many sedentary people will get anywhere near that!
November 27, 2024 at 7:45 PM