Cardio and VO2max
Cardiorespiratory fitness (often measured as VO2max or METs on a treadmill) is one of the strongest predictors of long-term survival in observational data. In Mandsager 2018, risk fell steadily from low to elite fitness with no observed ceiling. Trials show both steady endurance work and high-intensity intervals raise VO2max; in healthy adults the two were similar, with HIIT slightly ahead. Zone 2 (easy, conversational pace) is a popular base-building method; direct head-to-head trials of zone 2 versus HIIT on hard outcomes do not exist, so we treat it as one sensible tool, not a magic zone. [1][2][3]
How to maximize it
- 150-300 min/week moderate, or 75-150 min vigorous (US Physical Activity Guidelines).
- Most sessions easy (you can talk in full sentences); 1 session/week of intervals, e.g. 4 x 4 min hard with 3 min easy.
- Build volume gradually, about 10% per week.
Caveat: Fitness-mortality links are associational: healthier people may be fitter. Trials prove training raises VO2max, not that it adds a specific number of years.
Sources: [1] Mandsager K, et al. JAMA Netw Open. 2018;1(6):e183605 (Retrospective cohort, 122,007 adults, association); [2] Kodama S, et al. JAMA. 2009;301(19):2024-35 (Meta-analysis of 33 cohorts, 102,980 adults, association); [3] Milanović Z, et al. Sports Med. 2015;45(10):1469-81 (Meta-analysis of 28 controlled trials, 723 adults 18-45, trials)
Resistance training
Momma 2022 pooled 16 cohort studies: muscle-strengthening activity was associated with 10-17% lower risk of death and major diseases, with the biggest drop around 30-60 minutes per week and an unclear picture at much higher volumes. Combining strength and aerobic work was associated with the lowest risk. In randomized studies of adults 50+, resistance training raised strength by roughly 24-33%, more with higher intensity. [1][2]
How to maximize it
- 2-3 sessions/week, 30-60 min total of focused strength work, all major muscle groups.
- Compound lifts (squat or leg press, hinge, push, pull, carry); 2-4 sets of 6-12 reps, ending 1-3 reps short of failure.
- Add load or reps over time (progressive overload).
Caveat: Mortality data are from cohorts, mostly self-reported. Strength gains themselves are shown in trials.
Sources: [1] Momma H, et al. Br J Sports Med. 2022;56(13):755-63 (Meta-analysis of 16 cohort studies, association); [2] Peterson MD, et al. Ageing Res Rev. 2010;9(3):226-37 (Meta-analysis of 47 studies, 1,079 adults 50+, trials)
Grip, leg strength and muscle
In the PURE study (139,691 adults, 17 countries), each 5 kg lower grip strength was linked to 16% higher all-cause mortality. In the Health ABC study of adults 70-79, quadriceps and grip strength were strongly related to mortality while muscle size was not. Strength, a marker of muscle quality, appears to matter more than mass. Grip is a cheap marker, not a target in itself: the authors note it is unproven that improving strength lowers mortality. [1][2]
How to maximize it
- Train legs every strength session: squats, lunges, step-ups.
- Grip work for free: farmer carries and dead hangs, 2x/week.
Caveat: Associational. Low strength may reflect illness that already exists.
Sources: [1] Leong DP, et al. Lancet. 2015;386(9990):266-73 (PURE cohort, 139,691 adults, 17 countries, association); [2] Newman AB, et al. J Gerontol A. 2006;61(1):72-7 (Health ABC cohort, 2,292 adults 70-79, association)
Sit-to-rise test
Sit on the floor and stand up without using hands, knees or other support. Start at 10 and subtract a point for each support used. In 2,002 adults aged 51-80, lower scores were associated with higher mortality, and each one-point increase with 21% better survival. It mixes strength, balance and flexibility. [1]
How to maximize it
- Test yourself every few months on a soft surface, with someone nearby if balance is a concern.
- Practice: goblet squats, deep squat holds, hip mobility.
Caveat: Single Brazilian clinic cohort; associational. Skip it if you have joint problems or fall risk.
Sources: [1] de Brito LBB, et al. Eur J Prev Cardiol. 2014;21(7):892-8 (Retrospective cohort, 2,002 adults 51-80, association)
Steps per day
Paluch 2022 pooled 15 cohorts (47,471 adults). Compared with the lowest quarter (about 3,500 steps), higher quarters were linked to 40-53% lower mortality. Risk kept falling until about 6,000-8,000 steps a day for adults 60+ and 8,000-10,000 for adults under 60, then leveled off. [1]
How to maximize it
- Target 7,000-10,000 steps/day; add 1,000/day each week if you are below.
- Walk after meals and take calls on foot.
Caveat: Associational; people who walk more may already be healthier.
Sources: [1] Paluch AE, et al. Lancet Public Health. 2022;7(3):e219-28 (Meta-analysis of 15 cohorts, 47,471 adults, association)
Protein for muscle
Morton 2018 (49 RCTs) found protein supplementation increased strength and muscle gains from resistance training, with no further fat-free mass gains above about 1.6 g/kg/day. The benefit was smaller with age. Expert groups suggest 1.0-1.2 g/kg/day for healthy adults over 65 (PROT-AGE) and 1.4-2.0 g/kg/day for people who train (ISSN). [1]
How to maximize it
- About 1.2-1.6 g/kg/day if you lift, spread over 3-4 meals of 25-40 g.
- Food first; powder is a convenience. Kidney disease? Ask your clinician first.
Caveat: Gains are modest and depend on training; protein alone does not build muscle.
Sources: [1] Morton RW, et al. Br J Sports Med. 2018;52(6):376-84 (Meta-analysis of 49 RCTs, 1,863 adults, trials)
