SYNTH-104 · Guide

I have no race, I just want to be healthy: what do I do?

Reach 150-300 moderate minutes a week or 75-150 vigorous, lift twice, add balance; a beginner builds up over 12 weeks first. Once settled, keep some hard work and test every 8-12 weeks. Trials show fitness and function, not added years. Doses above the floor are practice.

Main caveat: Transfer. Almost no entry here is in trained people, so doses and curves are moved a long way.
limited evidenceMostly from non-athletes to highly trained athletes

The question it answers

An adult has no race and asks to train for health or a long life. What is in the week, how is the year laid out and judged without an event, what may be claimed, and what goes to a doctor?

Short answer: state the limit on years, reach the floor, add strength, balance and bone loading before adding hours, keep some hard work, test the qualities every 8-12 weeks and read them against age.

The assistant never promises added years, never gives a personal risk figure, never diagnoses, never advises on medication or supplements as treatment, and neither orders nor advises for or against a test or scan.

What this guide owns and what it leaves

Owns (decided here)Leaves to
What may be promised, and what the evidence on mortality does and does not showWhether and when to see a clinician before starting → REF-1319, SYNTH-75; competitive screening → REF-1071
The week's contents when health is the goal, and what comes before more hoursQuality-session counts → SYNTH-26; easy work, walks and commutes → SYNTH-51; first 12 weeks → SYNTH-75
Replacing the race with dated measures, and how to read them with ageSeason structure in general → SYNTH-76; order of blocks → SYNTH-90; test protocols and noise → SYNTH-53, SYNTH-91, SYNTH-93
The high-volume question: mortality, rhythm and plaque, as far as the base can sayStrength programming → SYNTH-43, SYNTH-44, SYNTH-101; masters recovery → SYNTH-35; the menopause transition → SYNTH-96; bone-like pain → SYNTH-94, SYNTH-73; weight and low energy availability → SYNTH-54; protein → SYNTH-69; sleep → SYNTH-07; smoking → SYNTH-100

Default — the decision, in order (what to prescribe first)

Not from a study; the base's own practice for the order and every step not given a source:

1

Ask what "health" means here, and route anything medical. Living longer, staying able, a number from a doctor or weight are different briefs. Ask about recent activity, known heart, metabolic or kidney disease or symptoms, and how hard they mean to go: those three decide who sees a clinician first, not age (REF-1319, A, consensus).

Routine preparticipation testing is not required for most asymptomatic individuals (REF-1528, A-, abstract). A named condition goes to the athlete's clinician.

2

Say the limit once, plainly. Whoever asks should hear what the evidence supports: fitness, strength and function in the people tested, not a number of years. See "What may be promised" below.

3

Reach the floor. 150-300 min of moderate or 75-150 min of vigorous aerobic work a week or a mix, strength on 2 or more days, and from 65 varied balance and strength work on 3 or more days (REF-1566, A+ process, general population, not written for athletes).

Moderate is about 3 to under 6 METs, RPE 12-13 on the Borg 6-20 (REF-1319's definitions), which is not the same as easy in SYNTH-51: a stroll can fall short, and a fit rider's easy ride can count as vigorous by activity type (REF-1570).

Below the floor, WHO says some is better than none: against none, all-cause mortality went with RR 0.77 at half the guideline dose and 0.69 at the guideline minimum (REF-1567, B+, self-report cohorts). The first steps are SYNTH-75.

4

Already above the floor: add what is missing before adding hours. Most riders and runners passed the aerobic line long ago (inference). Strength, balance and bone loading are what the sport leaves out, and adding them is the base's reading of the guideline, not a tested comparison.

5

Strength twice a week, all major muscle groups, with some heavy and some fast work. WHO asks for moderate or greater effort on 2 or more days; heavy and fast are the base's reading of trials inside older adults.

After 50, loads of 70% of 1RM or more built more leg strength than lighter ones, with wide intervals on falls (RR 2.68, 0.65-11.11) and adverse events (RR 2.42, 0.66-8.88) (REF-1086, A, abstract); high-velocity work raised power more than slow work in a meta-regression, and 2-3 sets on 2-3 days is the working dose there (REF-597, A+ as entered); a year of heavy lifting at retirement age left isometric leg strength above controls three years later, a secondary outcome, while leg power, the primary one, fell alike in all arms (REF-1139, A-), so power needs its own work (the entry's reading).

A first-time lifter spends 2-4 weeks at moderate loads learning the lifts first (practice; SYNTH-75, SYNTH-43). Cohorts place the lowest mortality near 40 min a week (RR 0.83) with very low certainty, and that is not a ceiling (REF-1572, B+).

Lifelong runners in their 70s, all men, had muscle more like active peers than lifelong lifters (REF-1190, B, cross-sectional, selection not excluded). Programming: SYNTH-43, SYNTH-44, SYNTH-101.

6

Balance work from midlife; from 65, WHO's 3 or more days of varied balance and strength. At 60 and over, balance and functional exercise cut the rate of falls (RaR 0.76, 95% CI 0.70-0.81; REF-1575, A, abstract; mean age 76); walking or resistance alone were uncertain, and endurance has no trial against control.

The abstract gives no programme dose, so a few minutes in a warm-up is practice for someone younger, not a trial dose; starting before 60 is practice too, and a rider or swimmer is a transfer (inference).

7

Load bone if the sport does not. Road cycling does not appear to build bone (REF-896, A-), and bone answers impact and heavy loads (PHYS-37, established).

The tested dose is supervised heavy lifting with impact, in postmenopausal women with low bone mass (REF-1405, A-, abstract); the outcome is density, not fractures, and no bone-loading trial here is in men or athletes. Heavy lifting without impact did not beat lighter lifting for density after 50 (REF-1086), so do not sell heavy as better for bone (SYNTH-35).

Putting that shape on the strength days for a rider or swimmer is practice; women around the last period: SYNTH-96. A rider's first running is new load for bone, started as a beginner runner (SYNTH-75), and jumps come after a strength base (SYNTH-45).

8

Keep some hard work in the plan. One hard session a week on four or more sessions is this guide's floor for a health goal (practice, like SYNTH-26's base-phase line). It sits below SYNTH-26's table, which gives 2 on four to seven sessions if recovery holds; that stays open, and on three sessions use its row. A true beginner needs none at first (SYNTH-26, SYNTH-75).

The support is indirect. Vigorous and moderate activity both went with lower mortality in 30 years of repeated questionnaires (REF-1570, B+), but vigorous there means activity type at 6 METs or more, so an easy ride counts and it is no evidence for intervals (the entry's inference). A maintenance review protects intensity first (REF-587, B+, general populations).

People in their seventies, healthy and already active, carried out 4 × 4-min sessions for five years with no cardiovascular events in supervised sessions, about half keeping to the protocol; over the five years heart attacks ran 16 in HIIT, 5 in moderate and 24 in the twice-as-large control arm, a crude contrast against moderate only, unplanned and untested in the paper: a signal to watch, not a finding (REF-1562, A).

9

Everything else that moves is welcome, and the week can be uneven. Light activity also went with lower mortality in accelerometer cohorts (REF-1569, B+, one measure, older samples, illness may drive both); which everyday rides and walks count as easy volume is SYNTH-51. Sitting: limit it and replace it with any activity; WHO could set no threshold (REF-1566).

One or two sessions a week against three or more at the same total: a difference was not shown, sameness was not tested (REF-1571, B+, abstract).

10

Lay the year out with measures instead of a race, and judge them against age (below).

What may be promised

ClaimSayEvidence
"Training will make me live longer"Not promised. Active and fit people live longer on average; whether training buys that, and how much, is not settledHigh vs low fitness: all-cause HR 0.47 to 0.59 (REF-1560, B+, cohorts, athletes excluded). Five years of supervised training after 70: 4.5% vs 4.7% deaths in active controls, HR 0.92 (0.58-1.47), so not shown and not excluded (REF-1562, A). A critical review reports no shown effect in about 50,000 older or chronically ill trial participants (REF-1563, B-, abstract). 180 identical twin pairs: HR 0.74, 99% CI 0.37-1.48 (REF-1564, B+). In 22,750 twins at most 7% lower risk remained after lifestyle and BMI (REF-1565, B+)
"Fitness and strength will improve"From a low base, yes, at the ages studied. A trained person may mainly holdAgainst doing nothing, combined training raised strength (SMD 0.74), power (0.50) and aerobic fitness (0.48) in healthy adults with mean ages of 50 to 73.5, training status unknown (REF-1524, A-)
"I'll stay independent"Independence was not the outcome. Trials show fewer falls at 60 and over and less loss of walking in sedentary 70-89-year-olds; younger or trained people are a transferFalls RaR 0.77 (0.71-0.83) at 60 and over, mean age 76; fall-related fracture RR 0.73 (0.56-0.95), low certainty, so "may" (REF-1575, A, abstract); fractures overall inconsistent (REF-1563). Losing the 400-m walk 30.1% vs 35.5%, HR 0.82 (0.69-0.98), over 2.6 years in sedentary people aged 70-89 with limitations; death not different, RR 1.14 (0.76-1.71); serious adverse events RR 1.08 (0.98-1.20), hospital stays not fewer (REF-1576, A)
"It will prevent diabetes"With diet, in people with prediabetes; a separate effect of exercise is lackingREF-1563, B-, abstract. A named risk or diagnosis is a clinician's
"It will sharpen my mind"Not promisedHealthy people: d = 0.22 falling to 0.05 (-0.09 to 0.14) after bias correction, and the reading is disputed (REF-1580, A-, abstract)
"My VO2max, grip or balance number predicts my death"They are markers of risk across groups, not personal forecasts or training targetsEach 1 MET higher went with 11-17% lower risk (REF-1560); 5 kg lower grip HR 1.20 in women, 1.16 in men, adding little to a risk score (REF-1573, B+); failing a 10-s one-leg stand HR 1.84 (1.23-2.78) (REF-1574, B, abstract). None shows that training the marker extends life; handgrip fell alike by year 4, three years after a supervised year of heavy lifting (REF-1139)
"Zone 2 is the longevity zone"No such zone is shown; no entry compares intensities for lifespanCurrent evidence does not support Zone 2 as the optimal intensity for mitochondrial capacity, and the review favours higher intensities at low volume (REF-1092, B+, narrative review, abstract; markers, not lifespan). Easy work has its uses: SYNTH-51
"My biological age is up"A marker. Do not change a plan for itAfter adjustment, clocks showed no benefit of activity, and the top class read 1.2-1.6 y older on one clock, in a mostly female subsample with possible under-reported smoking (REF-1565). App readings: SYNTH-91

How much is enough

"Hours" here concern health. Performance hours are SYNTH-26. Where the curves flatten, by source:

DoseMortality against noneSource and limit
Half the guideline (about 75 min moderate a week)RR 0.77 (0.73-0.80)REF-1567, B+, 94 cohorts, self-report
Guideline minimum (150 min moderate)RR 0.69 (0.65-0.73)REF-1567
Double the minimumRR 0.66 (0.62-0.70); beyond this differences were small and uncertainREF-1567
150-300 min vigorous or 300-600 min moderateHR 0.79-0.77 vigorous, 0.74-0.69 moderate, close to the lowest, the moderate curve still falling; no clear gain or harm aboveREF-1570, B+, repeated self-report, health professionals
3-5 and 5-10 times the minimumHR 0.61 (0.59-0.62) and 0.61 (0.58-0.64), the low pointREF-1568, B+, self-report once; gross METs, so its multiples do not map onto REF-1567
10 or more times the minimumHR 0.68 (0.59-0.78), no excess compared with noneREF-1568, only 4,077 people

Read this as a curve, not a target: the differences are between groups, people who are ill move less, and raw gaps shrink with adjustment (HR 0.50 adjusted for age alone against 0.81 after covariates, REF-1570). The base's practice: above the floor, hours are chosen for enjoyment and fitness, and no one is told extra hours add life, add nothing, or must stop.

A year with no race

Not from a study; the base's own practice. A fitness goal with dated tests and short blocks is already the line in SYNTH-76, goal-setting raised performance by 0.34 SD across sport studies with no bearing on health goals (REF-631, A, 36 older studies, often lab or short motor tasks, a transfer), and at equal load no block order has a reliable edge (SYNTH-90).

PieceDo thisNote
AnchorA test week every 8-12 weeks, on the calendar like an eventInterval is practice and longer than the 4-8 weeks of SYNTH-53, which tests at the end of each block; a rider who sets zones from the test keeps that rule. No entry validates either
Blocks3-6 weeks, 2-3 blocks adding up to the 8-12 weeks before a test, each with one emphasis: aerobic volume, ceiling, or strength; the others kept at a maintenance doseMaintenance: SYNTH-90, REF-587
Goal of a block2-4 plain measures from the table below, each with its start valueOne thing moves per block; the rest should hold (SYNTH-42). These are goals for fitness and function, not for lifespan: moving a marker is no claim about years
Lighter weeksOn recovery signals or as a planned week (SYNTH-29, SYNTH-30). No taper is neededAge alone does not set them (SYNTH-35)
BreaksKeep them short and keep a minimum going, the more so with age (inference, SYNTH-35); the return is SYNTH-36. No off-season is required; a lighter 2-4 weeks with some intensity kept is fine if wanted (SYNTH-76, practice)After 4-36 weeks off, older adults who had trained still did better than never-trained peers, less so the older they were; the length of the stop did not change that, so this sets no length (REF-1135, A-)
An event for funWelcome as a date to look forward to; it changes nothing above unless the goal changes, then SYNTH-76Practice
QualityMeasure, same protocol each timeHow to read it
Aerobic ceiling and thresholdA test from SYNTH-53, or a repeated climb or set effort on the same device. A newcomer's first test follows SYNTH-75, and someone inactive until recently uses the set effort, not a maximal one (REF-1319)A rise in the first years is common; later, holding or a slow fall is expected
StrengthEstimated or working loads from the gym log (SYNTH-101)Up or steady; train power as well, a heavy year did not protect it (REF-1139)
Balance and functionTimed stand on one leg, each side, safely beside support; from 65, or after a fall, also a timed walk or chair rises (practice)Above 50, not holding 10 s goes to the next medical visit; it is no diagnosis (REF-1574)
ConsistencySessions and weeks done against plannedThe base's first measure for this goal: nothing else in this table works without it (practice)
Weekly minutesAgainst the floor, plus strength and balance sessionsThe floor is met or not; more is a choice
Resting markersOnly if they already collect them, as trends (SYNTH-91)No target value

Read the numbers against age. On average every capacity peaked by 36 and fell 30-48% by 63, with a wide spread between people (REF-1138, B+, aerobic capacity estimated). Median lab VO2max was about 4 mL/kg/min lower each older decade (REF-1284, B+, abstract, cross-sectional).

Former elite runners, all men, all lost VO2max over 22 years, less if they kept training hard (REF-595, B, self-selected). So, past the early gains, a flat line or a slow fall over years is expected, not a stall (the base's reading of group curves; no entry tests holding as a goal).

These describe groups: the athlete's own repeat tests are the only trajectory that applies (SYNTH-35), a flat line says nothing while the floor is unmet or the sessions were not done, and small changes are noise until repeated (SYNTH-93). Do not compare a watch estimate with a lab table (SYNTH-91).

High volume and the heart

Someone who loves long hours asks if they are safe. Practice for the wording; no entry here sets a limit.

Mortality: no excess shown. 10 or more times the minimum, HR 0.68 against none (REF-1568). Lowest risk near 14 METs with no rise above it in 750,302 veterans (REF-1561, B+, abstract). The first 200 sub-4-minute milers lived longer than national life tables predicted (REF-1186, B), and French Tour de France riders had SMR 0.59 (0.51-0.68) (REF-1579, B, abstract).None of these separates training from selection, so read them as "not shorter", not "longer because of it".
Rhythm. Athletes had higher odds of atrial fibrillation than non-athletes, OR 2.46 (1.73-3.51), higher in mixed than in endurance sport, with no absolute risk or dose read and controls not described (REF-1577, B, abstract). A single case shows enlarged atria and later fibrillation, link unproven (REF-1185, C+).
Coronary plaque. In 558 low-risk men, amateurs training a median 10-11 h a week and mostly cyclists, lifelong endurance athletes more often had at least one plaque than healthy non-athletes, 63.4% vs 50%, OR 1.86 (1.17-2.94), and proximal non-calcified plaque, OR 2.80 (1.39-5.65); vulnerable plaque was rarer on few cases, OR 0.11 (0.01-0.98), stenosis was not significantly different, and no events were counted (REF-1578, B+, cross-sectional, men only).
What follows. Neither finding shows a safe or unsafe dose, so neither is a reason to cut training. Fitness does not clear blood pressure, lipids, smoking or family history: those stay worth checking with a doctor (SYNTH-100 for tobacco). The assistant does not advise for or against a scan or on medication: those questions go to their doctor.Scanning was not tested as a strategy here; the nearest line is that routine preparticipation testing is not required for most asymptomatic individuals (REF-1528, A-, abstract), which is not about a coronary scan in an athlete.

When to see a clinician

None of these is a diagnosis:

Chest, neck, jaw or arm discomfort, palpitations, dizziness or fainting, breathlessness out of proportion, or unusual fatigue with usual activity: stop and see a doctor before resuming, however fit (REF-1319; SYNTH-70). Collapse, or chest pain that does not settle with rest: emergency services (practice).
Known heart, metabolic or kidney disease and inactive, before starting; active with known disease, clearance in the last 12 months covers moderate work only (REF-1319). Any disease question about dose goes to their clinician.
A sudden unexplained loss of exercise capacity (practice; SYNTH-35).
Bone pain, a fragility fracture or known osteoporosis before heavy or impact loading (SYNTH-94; SYNTH-96). A question about a bone-density scan goes to a doctor too (practice; SYNTH-96).
Falls, or failing the one-leg stand after 50: mention it at a medical visit (practice; REF-1574).
Age alone is not a reason (REF-1319).

Practical Application

I have no race, I just want to be healthy: what do I do? Reach 150-300 moderate minutes a week or 75-150 vigorous, lift twice, add balance; a beginner builds up over 12 weeks first. Once settled, keep some hard work and test every 8-12 weeks. Trials show fitness and function, not added years. Doses above the floor are practice.
Laying out their season: say once that no years are promised, and put strength and balance in the plan, not only riding. Say that extra hours showed small and uncertain differences, not that they add nothing (practice).
"Is all this training hurting my heart?" Do not open with "probably not". No excess mortality in cohorts; higher odds of atrial fibrillation and more plaque; no safe or unsafe dose is known. Give both sides, proximal non-calcified plaque with the rarer vulnerable plaque on few cases. A scan result is read with their doctor, who decides about training (practice).
"How much for a long life?" Say the limit, then the curve: most of the difference sits up to about the guideline, little beyond (REF-1567). Do not give a personal figure.
A trained rider asking the same: the floor is passed. Offer strength, balance and bone loading before more hours; the hours stay their choice (practice).
Holding can be the result: past the early gains, tell them at the start that a flat line or a slow fall over years is expected and not a failure (practice). A beginner or someone below the floor can still expect to rise, a plateau needs a block that was done and two readings inside the noise (SYNTH-93), and a sudden loss goes to a doctor. The block's goal says "hold" where it means hold.

Key Findings — what the evidence shows

1

Fitness and activity are strongly associated with lower mortality, with the steepest part at the low end (REF-1560, REF-1561, REF-1567, REF-1568, REF-1569, REF-1570, all B+). Most of it is self-report or one baseline measure, and reverse causation and healthy-user bias are not excluded.

2

Trials and twins have not confirmed the mortality link. REF-1562 (A, active controls, few deaths), REF-1563 (B-, abstract), REF-1564 (B+, 87 deaths), REF-1565 (B+; within identical pairs one adjusted contrast held, moderately active vs sedentary). That is not shown, not disproved: the intervals allow a large benefit, the trials are in older or ill people, and none tests decades of habit.

3

Trials do show function, in older or untrained people. Falls (REF-1575, A), mobility (REF-1576, A), strength and power (REF-1524, A-; REF-1086, A), bone density in one tested group (REF-1405, A-).

4

Guideline. Aerobic range, strength 2+ days, balance and strength 3+ days from 65; more above the range is only a conditional recommendation (REF-1566, A+ process).

5

Strength is associated with lower mortality at modest doses, with very low certainty (REF-1572, B+); a trial of lifting against death is not in the base.

6

High volume showed no excess mortality, with non-fatal questions open (REF-1568, REF-1561, REF-1186, REF-1579; REF-1577, REF-1578).

It does not show: that training adds years to any person; a dose for health above the floor in trained people; that training a marker (VO2max, grip, one-leg stance, a clock) extends life; any trial of a no-race season, of test intervals, or of balance work in endurance athletes; that bone loading lowers fractures, or any bone-loading trial in men or athletes; a safe or unsafe lifelong volume; absolute rates of atrial fibrillation in amateurs; outcomes of coronary findings in athletes; women at high lifelong volume.

Conflicts and how they are resolved

Cohorts against trials and twins. Cohorts give large gradients; REF-1562, REF-1563, REF-1564 and REF-1565 do not confirm them. Resolved: state both, promise function, say "not shown" and not "no effect". The authors of REF-1560 and REF-1567 use causal language; REF-1563 says flatly that exercise does not prevent these outcomes. Both go further than their data, and the base uses neither wording.
[REF-1562]'s conclusion against its table. The authors suggest HIIT lowers premature death; HIIT vs control was HR 0.63 (0.33-1.20), exploratory. Resolved: hard work is kept for fitness and feasibility, not as a mortality claim.
Zone 2 or high intensity. REF-1092 argues against Zone 2 as optimal; SYNTH-51 uses easy work for volume. Resolved: no conflict for this goal. Easy work is what most people can repeat, some hard work stays in, and neither is called the longevity intensity. On the count, SYNTH-26's table gives 2 on four to seven sessions and this guide 1 as a health floor: both are practice, and the athlete chooses.
Strength: lowest point near 40 min a week against two days. REF-1572 finds a J shape at very low certainty and could not test frequency; REF-1566 recommends 2 or more days and found no dose-response evidence for more volume. Resolved: two short sessions a week as the default; 40 min is no ceiling.
"More is free" against "too much harms". REF-1568 and REF-1561 show no excess deaths; REF-1577 and REF-1578 show rhythm and plaque findings. Different outcomes. Resolved: no limit is set, and symptoms go to a doctor.
A hard session after 70. REF-1562 carried out 4 × 4 min in healthy, mostly active people with no supervised cardiovascular events; three fractures on slippery outdoor surfaces; heart attacks over five years ran 16 in HIIT, 5 in moderate and 24 in the twice-as-large control arm, unplanned and a signal to watch; REF-1319 warns about unaccustomed vigorous work in inactive people. Resolved: an inactive person builds up first (SYNTH-75); screening stays by REF-1319.

Limitations

Transfer. Almost no entry here is in trained people, so doses and curves are moved a long way. The cohorts' "most active" is often below a rider's ordinary week.
Practice: the order of steps, the test interval, block lengths, the session count above the floor and the measures table are not from studies.
Women and men: women few in REF-1561, absent from REF-1578, REF-1579, REF-1186, REF-595 and REF-1190; SYNTH-96 covers the menopause transition. Men: the falls trials are 77% women and the one bone-loading trial has none.
How this entry was checked and changed
Why this level

(the direction, reach the floor, then strength and balance, rests on a governing-body guideline REF-1566 (A+ for the process, moderate certainty and much of it observational for adult dose), randomised evidence on falls REF-1575 (A) and mobility REF-1576 (A), strength trials REF-1086 (A) and REF-1524 (A-), and bone evidence REF-1405 (A-) and PHYS-37 (established); the honest limit on mortality rests on REF-1562 (A), REF-1563 (B-) and REF-1564 (B+). Held at B because the mortality curves are cohorts at B+, nearly every trial is in untrained or older people, so all of it transfers to trained athletes, and putting these before more hours, the season layout, test intervals, session counts above the floor and the choice of measures are the base's practice. For a trained reader above the floor the default is practice and transfer, not a tested plan)

Revision notes
Written 2026-11-02 with REF-1560…1580.