In one sentence
A protocol is anything you do to yourself on purpose for recovery or stress, logged with its time and length so that your own record can show what tends to follow it.
What VT means by a protocol
Not training, which has its own log with intensity and effort, and not a supplement, which has its own with doses. A protocol is a practice: at launch, Breathwork, Cold shower, Mindfulness, Red light therapy and Sauna, and you can add types of your own. Each session is logged as a type, a time, a duration and a note, as a separate entry against the day.
Why log them
Because the only way to know whether a practice does anything for you is to see what your own readings do after it, often enough to tell a pattern from a coincidence. VT does not score protocols and does not reward you for doing them. It keeps them in your record beside your overnight readings, your sleep and your Capacity, so that after a few weeks the question "what happens to my HRV on the nights after a sauna" has an answer in your data rather than in someone else's.
What the evidence says, protocol by protocol
Breathwork: slow breathing has the clearest literature of the five. A meta-analysis of 223 studies found that voluntary slow breathing raised vagally mediated HRV during the session, immediately after a single session, and after multi-session programs (Laborde 2022), which makes it the one protocol whose effect you can expect to see in a reading the same night. Sauna: in Finnish cohort studies, frequent sauna bathing was associated with lower cardiovascular and all-cause mortality, and the review that gathered them proposed mechanisms in blood-vessel function, arterial stiffness, the autonomic nervous system and blood pressure, while noting that the evidence is observational and that people with conditions their doctor manages should ask first (Laukkanen 2018). Cold shower: in a randomized trial of 3,018 Dutch adults, finishing a hot shower with 30, 60 or 90 seconds of cold for a month reduced self-reported sickness absence from work by 29 percent, with no difference in the number of days people reported being ill and no serious adverse events, and 79 percent kept to the 30-day routine (Buijze 2016). Mindfulness: it has a large literature on sleep and stress that this entry does not summarize; it is in the list so that you can log it, and a later Knowledge Base article will take them properly. Red light therapy: the home-use evidence is thin and VT makes no claim for it; it is in the list for the same reason.
A caution about timing
A sauna, a hot bath or a hard breathwork session late in the evening can raise your overnight temperature and heart rate for that night. Symptom Radar does not yet give readings less weight for a logged protocol the way it does for alcohol or a late meal, so read the next morning's result with the session in mind, and prefer earlier in the day for the hot ones if a Yellow after a sauna bothers you.
How to log it well
At the time, with the real duration; a "sauna" that was eight minutes and a "sauna" that was thirty are different exposures. Use the note for what varied: temperature, rounds, a cold plunge after. Keep a type to one practice, and make a new type rather than stretching an old one, so that each type means one thing.
How Vitality Tracker uses it
Stored as entries against the day, beside that day's overnight readings, sleep and Capacity. Not scored, not an input to any engine, and not a Symptom Radar confounder.
Sources
- Laborde S, et al. Effects of voluntary slow breathing on heart rate and heart rate variability: a systematic review and a meta-analysis. Neurosci Biobehav Rev 2022;138:104711. doi:10.1016/j.neubiorev.2022.104711
- Laukkanen JA, Laukkanen T, Kunutsor SK. Cardiovascular and other health benefits of sauna bathing: a review of the evidence. Mayo Clin Proc 2018;93:1111–21. doi:10.1016/j.mayocp.2018.04.008
- Buijze GA, Sierevelt IN, van der Heijden BCJM, Dijkgraaf MG, Frings-Dresen MHW. The effect of cold showering on health and work: a randomized controlled trial. PLoS One 2016;11:e0161749. doi:10.1371/journal.pone.0161749
- Vitality Tracker, What VT measures (catalogue of 15 October 2026).