Let’s say that you are hoping to run a 4 hour marathon.
Daniel’s Tables will show you that the impact of race day temperature will have this kind of effect on your race time. Like this
| Temperature | 16° c | 18° c | 21° c | 24° c | 27° c | 29° c | 32° c | 35° c | 38° c | |
| Adjusted Time | 4:00:00 | 4:01:48 | 4:03:36 | 4:05:24 | 4:07:12 | 4:09:00 | 4:10:48 | 4:12:36 | 4:14:24 | |
| Adj Pace / km | 5:41 | 5:44 | 5:46 | 5:49 | 5:52 | 5:54 | 5:57 | 5:59 | 6:02 | |
Part of this extra slowness can be explained by a decline in fat oxidation as temperatures rise.
Anthocyanin supplementation can partly counteract this decline (and provide other benefits)
Studies released at the INTERNATIONAL SPORTS AND EXERCISE NUTRITION CONFERENCE (DEC 2018) showed that Anthocyanin supplementation increased fat oxidation by, on average, 30% compared to the placebo group under hot, ambient conditions.
The strategy that achieved this was to take 600mg of CurraNZ New Zealand blackcurrant extract for seven days before the exercise (race day).
*ALL* scientific findings to date on CurraNZ research are listed (here)
Get your Anthocyanin Discount (CURRANZ Discount) via this link below.I make zero money if you do get some (I know there is a cynical element out there). But I will be happy that you are just a little bit faster and I will be smug that I am doing my bit for aiding athletic awesomeness amongst the general population.
* Latin for ‘providing you don’
Last Updated on 20 January 2026 by the5krunner
My favourite kit and nutrition
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. ID
The pace decline looks very low to me. 2018 London Marathon (hot race day weather, but cold winter training) saw most friends ~20mins slower than expected.
I wonder if the table assumes athletes are well trained over the temperature range?
I thought this too, no way am I only 14 mins slower in 38-degrees compared to 16.
I think the table is just takes into account the fat oxidisation differences rather than the other issues temperature introduces.
hi
no it’s the standard Mr Daniel’s table from my collection. nothing to do with the people who make the product.
take it up with Mr Daniels! 😉