SFY Coach vs Sarvita
Sarvita describes itself as an AI longevity coach that turns your VO2 Max, HRV and body composition into one number — your biological age — then coaches you to lower it. It is genuinely good at the part it owns: if you already wear an Apple Watch, it reads what your body is doing without you logging anything, and it covers nutrition, cardio, strength, mobility and sleep in one place. It's free to download and the biological-age check costs nothing.
Pick Sarvita if
you're on an iPhone, you already wear a watch that tracks VO2 max and HRV, and the thing you want is one number that summarises all of it, updated continuously without you doing anything.
Pick SFY Coach if
you want the training itself, not the dashboard — and you want a measurement you performed rather than one your watch inferred. Five physical tests, a 22-week program a coach wrote, and the same five tests again at the end.
Side by side
| SFY Coach | Sarvita | |
|---|---|---|
| Category | A 22-week strength, balance and grip program | A longevity coaching app scored on biological age |
| Who it's for | Adults 45–65, plant-based or plant-curious | Longevity-minded iPhone users |
| The number it gives you | Youthspan score from five tests you perform — balance, floor sit-to-stand, dead hang, chair stand, reaction time | Biological age computed from VO2 max, HRV and body composition in Apple Health |
| Physical test | Yes — you do the five, at Week 0 and again at Week 22 | No — it reads what your devices already tracked |
| Named coach | Derek Tresize wrote every block and progression, and he's on the site | Kirill Shirinkin is named as the creator; the coaching itself is the app's |
| Plant-based method | Plant-first Daily Five, no gram targets, no weighing | Meal tracking from a photo, not built around one way of eating |
| Free option | Youthspan Snapshot, free with no account; then 3 days free with a card | Free download and a free biological-age check |
| Where it runs | Web app, works on any phone | iPhone, on Apple Health data |
Everything in the Sarvitacolumn is what they say about themselves on their own site, as of August 2026. If we've got something wrong, tell us and we'll fix it.
SFY Coach vs Sarvita — questions
Is a youthspan score the same thing as biological age?
No, and the difference is the whole reason to pick one over the other. Sarvita's biological age comes from what your watch measured — VO2 max, heart rate variability, body composition. A youthspan score comes from five things you actually do: stand on one leg, get off the floor, hang from a bar, stand up from a chair five times, and react to a signal. One tells you what your cardiovascular system looks like in the data. The other tells you what your body can still do on a Tuesday.
I don't have an Apple Watch. Can I still use SFY Coach?
Yes. Nothing here needs a wearable — the five tests need a chair, a wall, a bar to hang from and about ten minutes. If you do wear one, keep wearing it; we just don't ask it for anything yet.
Could I use both?
Plenty of people would. They answer different questions, and a biological-age number from your watch doesn't tell you what to train on Thursday. If you want to see how they compare, take the free Youthspan Snapshot — no account, no card — and put its five results next to whatever your watch has been telling you.