Anna Severova

21 articles

science running health training nutrition cycling

Author's articles

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 “runner'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 — but after the ultras euphoria did not rise at all. And endorphins, it seems, have nothing to do with any of it.

science running health

Anna Severova•Sep 21, 2026

Body Battery, Recovery, Readiness: 14 “readiness scores” from 10 brands — and not a single published formula

In May Google released the Fitbit Air, a screenless band whose headline number is “readiness”. 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.

recovery science training

Anna Severova•Sep 14, 2026

Creatine and hair loss: one 2009 experiment on rugby players versus a 12-week RCT with trichoscopy

The whole fear grew out of a single study: 20 rugby players, DHT +56% after a week of loading. Nobody counted any hair. Sixteen years later it was finally counted directly — 38 men, 5 g a day, a trichogram and FotoFinder. No difference from placebo, either in DHT or in hair density.

nutrition supplements health

Anna Severova•Sep 7, 2026

Urolithin A: 42 elite runners, “mitophagy” and a 3 km time trial that got no faster

The supplement is sold as a way to renew your mitochondria. In a double-blind trial on 42 high-level runners VO₂max rose by 5.4% versus 3.6% on placebo — but the statistics found no difference between the groups, and nobody's 3 km time improved.

running nutrition supplements

Anna Severova•Sep 1, 2026

Sleep trackers versus polysomnography: they catch sleep, they miss wakefulness

Six wristbands were tested in a sleep lab against PSG: sleeping epochs are recognised over 90% of the time, wakefulness only 29–52%. WHOOP overstates sleep time by 24 minutes, Apple Watch by 20. Here is what follows for your training.

recovery science training

Anna Severova•Aug 18, 2026

Heart rate zones in running and cycling: the average gap is 2 beats, the transfer error is 12

Across 5311 athletes, maximum heart rate on the bike came out just 2 beats lower than in running. But you still can't carry threshold zones from one sport into the other — and here's why the group average is useless.

training heart-rate science

Anna Severova•Aug 10, 2026

Five days of heat acclimation were not enough: what changed by the ninth

The critical heat limit a person can tolerate moved only after nine days of adaptation — after five there was no shift at all. Plus one more finding: you need a gap between the block and race day.

training science running

Anna Severova•Aug 7, 2026

Saddle height and knee pain: the 40 degrees past which the trouble starts

In cyclists with knee flexion greater than 40°, pain scored 4.4 on a ten-point scale; in the rest, 0.9. After the saddle was set to 25–30°, pain fell to 1.4 within two weeks. A look at the study and at what to do with the formulas.

science cycling injury-prevention

Anna Severova•Aug 7, 2026

Shoe rotation: 39% less injury risk — and why it isn't that simple

Runners who alternated between several pairs got injured noticeably less often. But there is only one study, it is more than ten years old, and it is observational. We unpack what you can take from it and what has been read into it.

injury-prevention running science

Anna Severova•Aug 6, 2026

Cycle Symptoms in Female Athletes: Why Asking “From Memory” Inflates Them Twofold

108 elite athletes kept a diary across 554 cycles. It turned out that retrospective questionnaires systematically exaggerate symptoms, and that not everything in training suffers — in football, high-speed work dropped off, while in cycling power did not change at all.

health training science

Anna Severova•Jul 30, 2026

Lactate gels: the biggest hype of the Tour de France — and what is actually known

Pogačar is racing on a gel with exogenous lactate and his rivals are testing their own. Yet there are no published trials of the gels themselves, and the existing work on lactate supplements contradicts itself. A look without the excitement.

nutrition science cycling

Anna Severova•Jul 29, 2026

Plus 55 minutes of sleep: what one extended night before a morning start gives you

In a crossover RCT participants slept 55 minutes longer — and the next morning covered almost 10 metres more in a shuttle test with half the drop-off in speed. Here is what is genuinely proven and what is being read into it.

recovery science training

Anna Severova•Jul 29, 2026

Beta-alanine: does the 'anti-acidosis' supplement work, and who actually needs it

Fresh 2026 meta-analyses show that beta-alanine's effect is narrow and not guaranteed. We break down where it can genuinely help, where it's useless, and how it differs from 'soda' (bicarbonate).

nutrition science running

Anna Severova•Jul 22, 2026

Blood flow restriction training: how light weights do the work of heavy ones

A cuff partially restricts blood flow, and loads of just 20–30% of your max deliver an effect close to heavy lifting. We break down where this genuinely helps a runner and why “cinching your leg with a belt” is a bad idea.

training science running

Anna Severova•Jul 18, 2026

Altitude training: why “live high — train low” doesn't work for everyone

Breaking down LHTL without the myths: how long you really need to live up high, why it won't work without iron, and what an amateur — not an elite marathoner — can realistically do.

training science running

Anna Severova•Jul 17, 2026

HRV training: how morning RMSSD tells you when to push and when to rest

Your morning RMSSD reflects how well you have recovered. Let’s look at what research says about training “by readiness” and how to measure HRV without fooling yourself.

training science running

Anna Severova•Jul 16, 2026

A Hot Bath Instead of Mountains: How Heat Raises VO₂max

Five weeks of post-run hot baths raised maximal oxygen uptake in trained runners by roughly 4,4%. We unpack how heat triggers the same blood and heart adaptations as altitude — and how to use it without the risk.

training science running

Anna Severova•Jul 15, 2026

Downhills wreck your legs: how your training background protects your muscles

A new study of trail runners found that those who regularly run downhill repeats damage their muscles less and better preserve their squat strength. We break down what this means for your training.

trail running training

Anna Severova•Jul 7, 2026

Caffeine before the start: how much you really need for a time trial

A large network meta-analysis of 48 studies shows the effective caffeine dose is more modest than commonly believed, and the performance gain is around 2%. Here is how to calculate your dose without overdoing it.

nutrition science running

Anna Severova•Jul 5, 2026

Hydration in sports: how much and what to drink before, during, and after exercise

The position stand of German sports nutritionists in plain terms: the working drink formula, fluid volumes, and why the advice 'drink before you're thirsty' is outdated.

hydration health science

Anna Severova•Jun 19, 2026

How Much Salt Is Safe: WHO Guidelines and Why It's More Complicated for Athletes

The WHO advises eating less than 5 g of salt a day, but during a multi-hour race in the heat that rule works in reverse. Let's figure out how to reconcile both approaches without harming your heart or cramping up on the course.

nutrition health science

Anna Severova•Jun 7, 2026