Can exercise keep an at-risk older person walking?
Yes in this trial: losing the 400 m walk 30.1% vs 35.5% (HR 0.82, 0.69-0.98) over 2.6 y, aged 70-89 and sedentary. No longer life shown. Athletes: a transfer.
Main caveat: Package and contact: the arms differ in staff attention, which may also affect recognition of events.
Screening of 14,831 people yielded 1635 randomised (818 vs 817): mean age 78.9, 67.2% women, BMI 30.2. Major mobility disability meant losing the ability to walk 400 m within 15 minutes without sitting or help from a person or walker. Persistent disability and the composite with death moved the same way. Hospitalisation did not fall, against the authors' expectation from observational cohorts, and neither did deaths.
Protocol
Physical activity arm: two centre visits plus home activity 3-4 times a week. Goal: 30 min of moderate walking daily, Borg 13 (150 min/week), 10 min of leg strength with ankle weights (2 sets of 10, Borg 15-16), 10 min of balance, plus flexibility.
Health education arm: weekly workshops for 26 weeks, then monthly, with 5-10 minutes of upper-limb stretching.
Delivered: attendance 63% (SD 27%), excluding medical leave, vs 73% (±25%); 58.6% of the exercise arm took medical leave at least once. Between-arm difference: 104 min/week (92-116) by self-report, 40 min/week (29-52) by accelerometer.
Assessment: every 6 months by blinded staff; outcome data for 97.1% vs 98.3%; loss to follow-up 4.0% a year. Powered for a 21-24% hazard reduction.
Funding and interests: NIH/NIA; the sponsor held 1 of 12 votes on the steering committee, which approved design, analysis and manuscript.
Key Results
| Outcome | Physical activity (n = 818) | Health education (n = 817) | Result (95% CI) |
|---|---|---|---|
| Major mobility disability | 246 (30.1%) | 290 (35.5%) | HR 0.82 (0.69-0.98), P = .03 |
| Persistent mobility disability | 120 (14.7%) | 162 (19.8%) | HR 0.72 (0.57-0.91), P = .006 |
| Disability or death | 264 (32.3%) | 309 (37.8%) | HR 0.82 (0.70-0.97), P = .02 |
| Serious adverse events | 404 (49.4%) | 373 (45.7%) | RR 1.08 (0.98-1.20) |
| Inpatient hospitalisation | 396 (48.4%) | 360 (44.1%) | RR 1.10 (0.99-1.22) |
| Death | 48 (5.9%) | 42 (5.1%) | RR 1.14 (0.76-1.71) |
| Fall causing a week of restricted activity (one row of an unadjusted safety table; hospital stays for fall, syncope, dizziness or vertigo: RR 1.02, 0.71-1.49) | 47 (5.7%) | 71 (8.7%) | RR 0.66 (0.46-0.94) |
Absolute: 5.4 points (authors), about 19 people treated for 2.6 years per case avoided (our arithmetic). The authors planned for a slightly larger effect and call this one clinically relevant.
Subgroups: no significant difference by race, sex, heart disease, diabetes, walking speed or function; SPPB <8, HR 0.81.
Alternative adjudication (no direct walk test possible) supplied 42 (17%) vs 32 (11%) of cases; sensitivity analyses for dropout moved estimates by less than 0.016.
Reporting, in the PMC author manuscript (the JAMA print was not checked). The text gives SPPB <8 as 71% of events, citing 283 of 536, but that is 52.8% (our arithmetic). In Table 2, 54 of 818 prints as 6.4%; it is 6.6% (our arithmetic). The abstract lists aerobic, resistance and flexibility; the methods add balance.
Mechanisms
Authors' interpretation: persistent disability fell more, read as prevention plus better recovery. Their explanations for hospitalisation (unmasked symptoms, closer contact, and exercise stress in vulnerable people, which they discount because results did not differ by baseline function) are hypotheses, and they allow that no causal link exists.
Inference: the accelerometer difference of 40 min/week is far smaller than the self-reported 104, but counts may miss ankle-weight and balance work, and the trial cannot say which component did the work.
Practical Application
Can exercise keep an at-risk older person walking? Yes in this trial: losing the 400 m walk 30.1% vs 35.5% (HR 0.82, 0.69-0.98) over 2.6 y, aged 70-89 and sedentary. No longer life shown. Athletes: a transfer.
Good for: a concrete template for an untrained older adult: daily walking at Borg 13, ankle-weight leg work, balance and flexibility, in people who had first passed a medical history, physical exam and resting ECG.
Good for: expectations: 58.6% took medical leave at least once, and the protocol planned restarts.
Not good for: a claim on mortality. Death RR 1.14 (0.76-1.71) fits either benefit or harm, as the authors say themselves.
Not good for: promising fewer hospital stays: RR 1.10 (0.99-1.22) overall and 1.17 (1.00-1.36) in those with SPPB ≥8, with no significant subgroup difference (P = .44).
Not from this paper; the base's own practice: symptoms or known heart, metabolic or kidney disease go to a clinician first (REF-1319); chest pain, palpitations, fainting: a doctor.
Limitations
Package and contact: the arms differ in staff attention, which may also affect recognition of events.
Unblinded participants; the health education arm also raised self-reported activity (34 min/week above baseline).
Selected volunteers, possibly self-referred (authors), mainly recruited by mailings.
Follow-up is short against an estimated life expectancy of 9 years (authors).
Not powered for death or hospitalisation.
How this entry was checked and changed
Why this level
large registered RCT (n = 1635), read from the full text (PMC copy), with an objective primary outcome and blinded assessors. It is one trial with a borderline primary result (P = .03), so it carries the mobility claim, not a general longevity claim