New US Step and Strength Guidance Is Coming. Rest Days Already Fit

On October 9, 2026, the US Department of Health and Human Services (HHS) filed a notice, set to publish in the Federal Register on October 13, saying it will add step-count and muscle-strengthening guidance to the Physical Activity Guidelines for Americans in 2027. Public comments are accepted until November 12. Until that supplement arrives, the 2018 guidelines apply, and they already make room for rest: for adults, the targets are weekly totals, not daily quotas. For most healthy adults, a planned day off doesn't put you behind if the week adds up, and a March 2026 American College of Sports Medicine (ACSM) position stand found that weekly training volume matters more for muscle growth than the number of training days.

Key takeaways

The 2018 US guidelines call for 150–300 minutes of moderate or 75–150 minutes of vigorous aerobic activity a week, plus muscle-strengthening on 2 or more days. Nothing in the adult guidelines requires daily exercise; children and teens aged 6 to 17 are the exception, with 60 minutes or more every day. The adult guidelines prefer aerobic activity spread over at least 3 days, partly to limit injury and fatigue.
The 2027 HHS supplement will cover steps and muscle-strengthening; whether it will address rest days is not yet known.
The 2026 ACSM stand (137 systematic reviews, more than 30,000 people) favors 2 or more sessions a week for strength. Muscle growth was similar with 1 or more than 5 training days a week at equal weekly volume. The stand does not address how much time to leave between sessions.
In large observational studies of 350,978 US adults and 89,573 UK adults, people who got their activity in 1–2 sessions a week (US) or at least half of it on 1–2 days (UK) had risk patterns similar to people who spread it out.
Wearable recovery scores typically draw on overnight heart rate variability readings, whose average error ranged from about 6% to 16% across five devices in a 2025 study.

What it means for you

Just starting: Rest days are part of the plan. Build up gradually; the sample week below is a starting point.
Strength training: For strength, aim for at least two sessions a week. For muscle size, weekly sets matter more than the number of days (see the FAQ).
Runners and endurance athletes: Overload needs matching recovery; warning signs are under "When you need more than a day off."
Adults 65 and older: The weekly targets are the same as for younger adults, with balance training added. If chronic conditions make 150 minutes impossible, the guidelines say to be as active as your abilities and conditions allow. Older adults take longer to adapt to a new activity level (see the FAQ).
Parents: The weekly-total approach is for adults. Children and teens aged 6 to 17 are advised to get 60 minutes or more of activity every day.
Weekend warriors: Studies link your pattern with benefits similar to spreading activity out, though the guidelines prefer three or more days.
Fitness tracker users: A readiness score is a hint, not a verdict; see the section on recovery scores.
Chronic conditions: The guidelines advise being under a health care provider's care. For some conditions, such as ME/CFS, the usual exercise advice does not apply.

What the guidelines actually say

The idea is older than the headline: US guidance has set weekly amounts since its first edition in 2008. What is newer is evidence on how much timing within the week matters.

Date	Source	What it says about frequency and rest
2011	ACSM position stand on exercise quantity and quality	Resistance exercise for each major muscle group on 2–3 days a week. Moderate cardio on 5 or more days, or vigorous cardio on 3 or more.
2018	HHS Physical Activity Guidelines, 2nd edition	Weekly targets. Spread aerobic activity over at least 3 days. Build up in small steps and give the body time to adapt and recover.
Mar 2026	ACSM resistance training position stand	2 or more sessions a week for strength. Training frequency did not change muscle growth once weekly volume was equal.
Oct 9, 2026	HHS Federal Register notice	Calls for comments on a 2027 supplement on steps and muscle-strengthening.

The current Physical Activity Guidelines for Americans, 2nd edition set adult targets as weekly amounts (children and teens aged 6 to 17 get a daily target of 60 minutes, page 48). They say that spreading activity over at least 3 days may help reduce injury risk and prevent excessive fatigue (page 58). The safety chapter adds that a small overload followed by time to adapt and recover reduces injury risk (page 90). The WHO 2020 guidelines use the same 150–300 and 75–150 minute weekly ranges. The 2011 ACSM stand set day counts per exercise type, whose minimums also leave room for days off.

The HHS notice (docket HHS-OASH-2026-0463) asks for evidence on steps and muscle-strengthening. It does not propose any new numbers. HHS had said in October 2024 that a full third edition was not expected before 2028.

Weekly totals versus daily streaks

Large studies have compared people who get their weekly activity in one or two sessions with people who spread it out:

An analysis of 63,591 adults aged 40 and over in England and Scotland (2017) found lower all-cause and cardiovascular death rates than in inactive people for both "weekend warriors" and the regularly active.
A US study of 350,978 adults (2022) found that, at the same total activity, weekend warriors' death rates did not differ significantly from the regularly active (hazard ratio 1.08; 95% confidence interval 0.97–1.20). One caution: compared with inactive people, the regularly active had a clearly lower death rate (hazard ratio 0.85), while the weekend warriors' lower rate (0.92; 0.83–1.02) was not statistically significant on its own.
A UK Biobank study (2023) had 89,573 people wear a movement sensor for a week. Among those reaching 150 minutes, more got at least half of it in 1–2 days (42.2% of the sample) than spread it out (24.0%), and both groups had similarly lower risks of atrial fibrillation, heart attack, heart failure and stroke. A 2024 follow-up tested 678 conditions and found none where the two patterns differed significantly.

These studies are observational: they show associations, not cause and effect. They point to the weekly total, not a daily streak, as what tracks with long-term benefit. The guidelines' preference for three or more days rests partly on limiting injury and fatigue, so it still suits people who are building up.

Strength training looks similar. The 2026 ACSM position stand found that muscle growth was similar with low (1 day a week) and high (more than 5 days a week) frequency when total volume was the same. Strength improved more with at least 2 sessions a week, with too little evidence to say more sessions keep adding benefit. Resting under 1 minute or over 1 minute between sets made no difference to strength gains (there was too little data to judge the effect on muscle size). The stand does not address how much time to leave between sessions, so it neither sets nor rules out a minimum gap.

A sample week with two rest days

By the HHS rule of thumb, 2 minutes of moderate activity count the same as 1 minute of vigorous activity:

weekly aerobic total (moderate-equivalent minutes)
  = moderate minutes + 2 × vigorous minutes
target: 150 to 300

On the guidelines' 0-to-10 effort scale, where sitting is 0 and an all-out effort is 10, moderate activity such as brisk walking is a 5 or 6. Vigorous activity such as running starts at 7 or 8. Muscle-strengthening sessions count separately and generally do not add to the aerobic total.

Illustrative example. A plan for someone working toward the minimum:

Day	Activity	Counts toward
Monday	30 minutes of strength work for all major muscle groups (bands, body weight or weights)	Strength day 1
Tuesday	45-minute brisk walk	45 moderate
Wednesday	Rest	None
Thursday	30 minutes of strength work	Strength day 2
Friday	Rest	None
Saturday	60-minute easy bike ride	60 moderate
Sunday	45-minute brisk walk	45 moderate

Total: 45 + 60 + 45 = 150 moderate minutes on 3 days, plus 2 strength days, with 2 full rest days. This meets the minimum and the guidelines' suggestion to spread aerobic activity over at least 3 days. The two strength sessions are 3 days apart.

Two other ways to reach the same weekly target:

Vigorous version: Three 25-minute runs (Tuesday, Thursday and Saturday) give 75 vigorous minutes, or 75 × 2 = 150 moderate-equivalent minutes. Adding strength work after two runs leaves 4 rest days.
Weekend version: A 90-minute hike on Saturday and a 60-minute ride on Sunday give 150 minutes on 2 days. With strength work on Tuesday and Thursday, that leaves 3 rest days. The studies above link this pattern with similar benefits, though the guidelines prefer 3 or more days.

All three meet the same weekly target with two to four rest days; what changes is how hard each session is.

What recovery scores can tell you

Many watches and rings give a daily "readiness" or "recovery" score. These scores typically draw on overnight measurements such as resting heart rate and heart rate variability (HRV). HRV is the variation in time between heartbeats. A 2025 study funded by the Air Force Research Laboratory compared overnight readings from five devices with a chest-strap ECG. It covered 13 healthy adults over 536 nights. Average HRV error by device:

Device tested	Average HRV error vs ECG
Oura Gen 4 ring	5.96%
Oura Gen 3 ring	7.15%
WHOOP 4.0	8.17%
Garmin Fenix 6	10.52%
Polar Grit X Pro	16.32%

The study tested the raw measurements, not the scores. Its authors note that each device uses proprietary algorithms and that there is little transparency into which metrics feed each brand's readiness or recovery score. The study did not test whether the scores themselves predict recovery. The participants were healthy, and the authors point out that irregular rhythms such as atrial fibrillation affect HRV readings.

Is planning training around HRV worth it? A 2021 meta-analysis pooled 8 endurance studies with 198 participants. HRV-guided plans usually included fewer moderate and hard sessions, gave a medium-sized benefit on submaximal fitness measures and only a small, non-significant gain in performance, with fewer people failing to improve. Given errors of several percent per reading, a pattern over several days is a sturdier signal than one low score.

When you need more than a day off

The ECSS–ACSM overtraining consensus separates short-term fatigue that turns into better performance after recovery, which is expected, from persistent fatigue, falling performance and mood changes, which are not. No single blood test or score reliably confirms overtraining. Diagnosis means first ruling out other causes, including illness, eating too little for the training load and iron deficiency.

Underfueling has its own name. The 2023 International Olympic Committee consensus calls it Relative Energy Deficiency in Sport (REDs). It describes harm to health and performance in both women and men when food intake does not cover exercise needs.

Sleep is part of recovery too. The American Academy of Sleep Medicine and Sleep Research Society recommend that adults aged 18 to 60 sleep 7 or more hours a night on a regular basis.

This article is general education, not medical advice. The HHS guidelines advise anyone who develops new symptoms while increasing activity to consult a health care provider (page 93). The same applies if fatigue or falling performance continues after you cut back. For people with ME/CFS, CDC clinical guidance warns that standard exercise recommendations for healthy people can substantially harm patients and recommends pacing activity and rest within personal limits.

Frequently asked questions

Is an easy walk better than a completely restful day?

The evidence on light activity right after exercise is mixed. A 2018 meta-analysis of 99 studies found that active recovery reduced muscle soreness, and massage was the most effective method studied. A 2018 narrative review of cool-downs found them largely ineffective for most recovery markers and not shown to prevent injury. On a rest day, an easy walk is fine if it feels good, but it is not required.

Can I lift weights two days in a row?

The 2026 ACSM stand does not address how much time to leave between sessions, so it gives no minimum gap either way. It found that muscle growth depends on weekly volume, about 10 or more sets per muscle group per week, more than on how many days you train. One option, not an ACSM recommendation, is to train different muscle groups on back-to-back days, which spreads that volume without working the same muscles twice in a row. If soreness from one session is still affecting the next, take that as a reason to space them out.

Does a rest day mean sitting most of the day?

No. The HHS guidelines tell adults to move more and sit less throughout the day, and the 2011 ACSM stand notes benefits from breaking up sitting even in people who exercise regularly. A rest day means no structured training, not no movement.

How much does sleep matter for recovery?

Quite a lot, based on short-term studies. In a 2021 lab study of 13 young adults, one night without sleep cut muscle protein synthesis (the process that repairs and builds muscle) after a meal by 18%, and cortisol rose by 21%. It was a small study of total sleep loss, but it is consistent with the consensus target of 7 or more hours a night.

Do older adults need to progress more slowly?

Yes, according to the HHS guidelines (page 90). They say older adults appear to need 2 to 4 weeks to adapt to a new level of activity, while youth and young adults can probably increase by small amounts every week or two. Older adults are also advised to include balance training in their weekly activity.

Planning rest into your week

Add up last week's moderate minutes plus 2 × vigorous minutes, and count your strength days. If you reached 150 minutes and 2 strength days, the guidelines leave the remaining days up to you.
If you add activity, add a little at a time. HHS gives the example that adding 20 minutes is a 10% increase for someone doing 200 minutes a week, but a 50% increase for someone doing 40.
If you use a tracker, weigh its several-day trend and how you feel over a single day's score.
If you would like a say in the 2027 supplement, comments go to docket HHS-OASH-2026-0463 by 11:59 p.m. ET on November 12, 2026.