AS

Anna Severova

24 articles

Author's articles

Can’t sleep after evening intervals? What 4 million nights and a 2026 meta-analysis show

Can’t sleep after evening intervals? What 4 million nights and a 2026 meta-analysis show

After a hard evening workout some people lie awake for ages, while others fall asleep instantly and wake up at four in the morning. A 2026 meta-analysis of randomised trials and data from 14,689 people wearing fitness bands agree: the problem is not the time of day as such, but intensity and how many hours are left before bed. We go through the numbers and what to do with them.

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Creatine without training: 1.1 kg more lean mass in 12 weeks in 45–65-year-olds β€” and how much of it may be water

Creatine without training: 1.1 kg more lean mass in 12 weeks in 45–65-year-olds β€” and how much of it may be water

In a double-blind RCT from Texas A&M University, 10 grams of creatine a day added about a kilogram of lean mass and a little strength in people aged 45–65, even without training. We look at why the no-training groups had just 13 people each, what DXA counts as β€œmuscle”, how creatine skews the creatinine blood test, and what a masters runner should take from it.

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The runner's high: anandamide rises every 14 kilometres of a marathon, and after 230 kilometres there is no euphoria left

The runner's high: anandamide rises every 14 kilometres of a marathon, and after 230 kilometres there is no euphoria left

A 2026 field study followed the β€œrunner's high” across a whole marathon for the first time: 19 runners gave blood every 14 km, and another 36 ultrarunners before and after races of 100, 160 and 230 km. Anandamide rose all the way, anxiety fell β€” but after the ultras euphoria did not rise at all. And endorphins, it seems, have nothing to do with any of it.

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Body Battery, Recovery, Readiness: 14 β€œreadiness scores” from 10 brands β€” and not a single published formula

Body Battery, Recovery, Readiness: 14 β€œreadiness scores” from 10 brands β€” and not a single published formula

In May Google released the Fitbit Air, a screenless band whose headline number is β€œreadiness”. Garmin, WHOOP, Oura, Polar and Coros all have similar indices. A 2025 review found 14 such scores from 10 manufacturers: none disclosed its formula, and only a handful showed validation against a reference standard. Some of the raw data underneath them, however, is measured quite well.

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