Reference · 28 terms · Last reviewed 2026-05-04
Longevity Glossary.
The terms that show up across hardware reviews, supplement coverage, and protocol pages — defined in plain English, without medical claims.
A
- AMPK
- AMP-activated protein kinase, an enzyme that acts as a metabolic master switch. AMPK activates when cellular energy is low and stimulates fat oxidation, autophagy, and mitochondrial biogenesis. Caloric restriction, exercise, metformin, and berberine all activate AMPK. In longevity contexts, AMPK is often discussed as a counterweight to mTOR signaling — high AMPK activity broadly correlates with cellular maintenance over growth.
- Autophagy
- A cellular recycling process by which damaged proteins and organelles are broken down and reused. Autophagy is upregulated by fasting, exercise, and certain compounds (rapamycin, spermidine). It declines with age, and impaired autophagy is implicated in neurodegeneration and metabolic disease. Many longevity protocols are designed to periodically trigger autophagy through fasting windows or pharmacological mimetics.
B
- Biomarker
- A measurable indicator of biological state — blood-based (e.g. ApoB, HbA1c, hs-CRP), imaging-based (DEXA body composition, coronary calcium score), or wearable-derived (HRV, resting heart rate). In longevity practice, biomarkers are used to track intervention impact over time. The MyProtocolStack platform is built around longitudinal biomarker tracking; many of the diagnostics covered on Lifespan Vault produce biomarkers.
- BPC-157
- A synthetic peptide derived from a protein found in human gastric juice, named “Body Protection Compound”. Used informally for soft-tissue and tendon recovery. BPC-157 is not FDA-approved for human use; it is sold through compounding pharmacies and the research-chemical channel. Lifespan Vault tracks peptides as a category but does not make medical claims about dose, indication, or outcome.
C
- Contrast therapy
- Alternating exposure to hot (sauna, hot tub) and cold (cold plunge, cold shower) within a single session. Practitioners use contrast cycles to drive vascular adaptation, sympathetic-parasympathetic shifts, and recovery between training sessions. Common protocols use 3–4 hot/cold cycles ending on cold. Most cold-plunge and sauna hardware Lifespan Vault covers can be paired into a contrast setup.
- Cryotherapy
- Whole-body cold exposure delivered through specialized chambers cooled to roughly −110°C to −140°C using nitrogen vapor or refrigeration. Sessions last 2–4 minutes. Cryotherapy is distinct from cold-water immersion (cold plunge), which is wetter, longer, and operates at much warmer temperatures. We treat them as separate categories with different scoring rubrics.
E
- EMS (electrical muscle stimulation)
- A modality that uses electrical impulses to trigger muscle contraction without voluntary effort. EMS hardware ranges from clinical neuromuscular-rehabilitation devices (Compex, NEUFIT) to consumer recovery wearables (Therabody, Hyperice EMS sleeves). Quality varies widely; we score on waveform control, pad longevity, and app integration in our forthcoming EMS rubric.
F
- Far-infrared
- The portion of the infrared spectrum with wavelengths roughly 3,000–100,000 nm, perceived primarily as heat. Far-infrared saunas use heaters that emit predominantly in this range and are typically sold as “low-EMF” or “solo” cabin setups. Far-infrared penetrates skin shallowly compared to mid- or near-infrared, and the heating effect is gentler at lower cabin air temperatures.
G
- GLP-1
- Glucagon-like peptide-1, an incretin hormone released by the gut after eating that stimulates insulin secretion and signals satiety. GLP-1 receptor agonists (semaglutide, tirzepatide) are FDA-approved for type-2 diabetes and obesity; they are also widely prescribed off-label and through telehealth. Lifespan Vault covers the diagnostic and tracking infrastructure around GLP-1 use without making outcome claims.
H
- HBOT (Hyperbaric Oxygen Therapy)
- A modality in which a person breathes oxygen at pressures above sea level — typically 1.3 to 3.0 atmospheres absolute (ATA) — inside a sealed chamber. Soft-shell chambers operate around 1.3 ATA; hard-shell medical-grade chambers reach 2.0+ ATA. HBOT has FDA-cleared indications for specific medical conditions; non-clinical longevity use is off-label. We score chambers on pressure capability, oxygen integration, and safety certification.
- HRV
- Heart-rate variability, the variation in time between consecutive heartbeats, typically reported in milliseconds (rMSSD or SDNN). Higher HRV broadly correlates with parasympathetic tone, recovery state, and cardiovascular fitness. Most longevity wearables (Whoop, Oura, Apple Watch, Garmin) report nightly or continuous HRV. Sensor-quality differences across wearables are large; HRV accuracy is a major scoring criterion in our wearable rubric.
I
- Infrared sauna
- A sauna heated by infrared emitters (carbon panels, ceramic rods, or full-spectrum tube heaters) rather than a stove heating air and rocks. Cabin air temperatures are lower than traditional saunas (typically 110–150°F vs 170–200°F), with the heating effect coming from radiant infrared on skin. Subdivides into far-, mid-, and near-infrared depending on heater spectrum.
M
- Metformin
- A first-line oral medication for type-2 diabetes that lowers hepatic glucose production and improves insulin sensitivity, partly via AMPK activation. Metformin has been studied as a healthspan compound (the TAME trial) but is not FDA-approved for longevity use. It is widely prescribed off-label by longevity-focused clinicians; Lifespan Vault tracks the diagnostic and lab-monitoring infrastructure around its use.
- mid-infrared
- The portion of the infrared spectrum roughly 1,400–3,000 nm. Mid-infrared penetrates tissue more deeply than far-infrared and is sometimes targeted in full-spectrum sauna heaters for circulatory and soft-tissue effects. Pure mid-infrared cabins are rare; most consumer hardware blends mid- with near- and far-infrared in a single full-spectrum heater.
- mTOR
- Mechanistic target of rapamycin, a protein kinase that integrates nutrient and growth-factor signals to regulate cell growth and protein synthesis. Sustained mTOR activation accelerates cellular aging in model organisms; mTOR inhibition (via fasting, caloric restriction, or rapamycin) extends lifespan in mice. mTOR is the counterweight to AMPK and autophagy in most longevity discussions.
N
- NAD+
- Nicotinamide adenine dinucleotide, a coenzyme central to mitochondrial energy production and to the activity of sirtuins and PARPs. NAD+ levels decline with age. NAD+ precursors (NMN, NR) are sold as supplements with the goal of restoring tissue NAD+ pools. Lifespan Vault covers diagnostics that quantify NAD+ status and supplements that target this pathway, without making outcome claims.
- near-infrared
- The portion of the infrared spectrum roughly 700–1,400 nm. Near-infrared penetrates tissue deepest of the three IR bands and is used in red-light therapy panels (often paired with red 660 nm) for stated effects on mitochondrial function and tissue repair. The 850 nm wavelength is the most-used near-infrared band in panel products we cover.
- NMN
- Nicotinamide mononucleotide, a precursor in the NAD+ biosynthesis pathway. NMN is sold as an oral supplement; its regulatory status in the United States is contested (the FDA reclassified NMN as a drug in 2022, though enforcement has been limited). Lifespan Vault covers NMN as a supplement category and tracks the regulatory situation in coverage updates.
P
- PEMF
- Pulsed electromagnetic field therapy. PEMF devices generate low-frequency electromagnetic pulses applied to the body via mats, coils, or rings. Marketed for circulatory, recovery, and bone-density use. Field strength and frequency vary widely across consumer-grade and clinical hardware; our forthcoming PEMF rubric scores on field-strength validation, pulse-shape control, and warranty depth.
- Peptides
- Short chains of amino acids (typically 2–50) that act as signaling molecules in the body. The category includes FDA-approved drugs (semaglutide, tirzepatide, sermorelin), research peptides (BPC-157, TB-500), and a long tail of compounds sold through compounding pharmacies. Lifespan Vault covers the diagnostic and tracking infrastructure around peptide protocols; the MyProtocolStack platform is purpose-built for peptide tracking.
- Photobiomodulation
- The umbrella scientific term for the application of red and near-infrared light to tissue to elicit biological response, primarily via cytochrome c oxidase in mitochondria. Photobiomodulation is the mechanism behind “red-light therapy.” Dose is a function of irradiance (mW/cm²), wavelength, distance, and exposure time — all measurable variables we score in our red-light rubric.
R
- Rapamycin
- A macrolide compound originally isolated from soil bacteria on Easter Island, currently FDA-approved as an immunosuppressant under the name sirolimus. Rapamycin is the pharmacological inhibitor of mTOR and one of the most-studied compounds in mammalian-aging research. Off-label longevity prescribing is increasing through specialized clinics; Lifespan Vault tracks the lab-monitoring infrastructure around its use.
- Resting heart rate
- The number of heartbeats per minute at rest, ideally measured at the same time each day under consistent conditions. Lower resting heart rate broadly correlates with cardiovascular fitness, parasympathetic tone, and recovery state. Most longevity wearables track resting heart rate continuously; trend changes over weeks are usually more informative than absolute values.
S
- Senolytic
- A compound that selectively induces apoptosis in senescent cells — “zombie” cells that have stopped dividing but resist death and secrete pro-inflammatory factors. Studied senolytics include dasatinib, quercetin, fisetin, and the natural product navitoclax. Most senolytic protocols use intermittent dosing. Clinical evidence for long-term outcome is early-stage; Lifespan Vault covers the diagnostics around senescence without making outcome claims.
- Sermorelin
- A growth-hormone-releasing-hormone analog used to stimulate endogenous growth hormone production. Sermorelin is FDA-approved for pediatric growth-hormone deficiency and is also prescribed off-label through longevity and anti-aging clinics. Like other peptides, Lifespan Vault covers it as a category and tracks the diagnostic infrastructure (IGF-1 testing, lab cadence) without making outcome claims.
- Spermidine
- A naturally occurring polyamine present in wheat germ, aged cheeses, and fermented foods. Spermidine induces autophagy and has been associated with cardiovascular and longevity outcomes in observational and rodent studies. Sold as a supplement (often as wheat-germ extract). Lifespan Vault covers spermidine alongside other autophagy-targeting compounds in the supplement category.
U
- Urolithin A
- A metabolite produced by gut bacteria from ellagitannins (found in pomegranates, walnuts, certain berries). Urolithin A is studied for its effects on mitophagy — the recycling of damaged mitochondria. Direct supplementation (e.g. Mitopure / Timeline Nutrition) bypasses the need for the right gut-microbiome composition. Sold as a supplement; we cover the category without making outcome claims.
V
- VO2max
- The maximum volume of oxygen the body can use during intense exercise, measured in mL of O2 per kg of body weight per minute. VO2max is one of the strongest single predictors of all-cause mortality. Measured most accurately by graded-exercise lab testing; estimated less precisely by wearables (Apple Watch, Garmin, Polar). VO2max trend over time is one of the highest-signal biomarkers in longevity practice.
Missing a term? Email ryan@lifespanvault.com with the term and a sentence about how you’ve seen it used. Definitions get added in batches; the next update lands with the v1.1 test protocol release. Related: LV Test Protocol · editorial policy.