What actually has to happen in a week

The weekly targets are the same whether you are inside or outside. The Centers for Disease Control and Prevention and the American Heart Association both describe the adult goal as 150 minutes a week of moderate intensity aerobic activity, or 75 minutes of vigorous intensity activity, or a mix of the two. The federal guidelines give a range of 150 to 300 minutes of moderate activity per week, and the American Heart Association notes that more benefit comes with at least 300 minutes.

On top of that, both recommend muscle strengthening activity on at least 2 days a week. CDC is specific about what those sessions should cover: all the major muscle groups, meaning legs, hips, back, abdomen, chest, shoulders, and arms.

Moderate intensity is easier to judge than most people expect, and you do not need a device to do it. The American Heart Association describes the talk test this way: at moderate intensity your heart beats faster and you breathe harder than normal, but you can still talk. At vigorous intensity you cannot say much without getting out of breath. Indoors, where there is no hill and no headwind to gauge yourself against, the talk test is the single most useful tool you have.

CDC puts the scheduling part simply. You do not have to do it all at once, and 30 minutes a day on 5 days is only one way to get there. The National Institute on Aging goes further for people managing a health condition, suggesting that several short "mini workouts" may work better than one long session.

A bad weather week usually goes wrong in two ways at once. The planned activity disappears, and the sitting quietly expands to fill the space. The American Heart Association addresses the second half directly, advising people to spend less time sitting and noting that even light intensity activity can offset some of the risks of being sedentary. The first key message in the federal guidelines is to move more and sit less. A separate article in this series covers planning movement breaks during a desk day.

Indoor places that are already open

Most towns have more weather proof walking space than people realize. The trick is knowing the hours and the rules before you show up in the rain.

1. 1 Shopping malls. Many open their doors to walkers before the stores start business. Floors are level, the temperature is fixed, there are restrooms and benches, and there is no traffic. Call the mall management office rather than a store to ask about early entry hours and whether there is an organized walking group.
2. 2 Community centers, senior centers, and parks department buildings. These often have a gym floor, a short indoor track, or a multipurpose room, and fees are frequently lower than a private gym. Some run classes you can watch once before joining.
3. 3 School and college recreation centers. Indoor tracks are sometimes open to the public during set hours, occasionally free for residents or older adults.
4. 4 Large stores with wide aisles. Not glamorous, and not a substitute for a track, but a supercenter or home improvement store is dry, well lit, and long enough to accumulate real minutes.
5. 5 Houses of worship and fraternal halls. Fellowship halls and gymnasiums are empty most weekday mornings, and many congregations will open them for a small group.
6. 6 Hospital, medical campus, and downtown skywalks. Long enclosed corridors exist in many cities. Ask at the front desk whether walking is allowed and where.
7. 7 Indoor pools. A pool at a community center, a hospital rehabilitation department, or a school is the most weather proof option of all.

Five questions can cover the main points in a single phone call: what hours can I use the space, is there a fee or do I have to be a member, how far is the door from the parking, are restrooms and benches on the same level as the walking area, and when is it quietest.

If mobility limits shape which places will work, the National Center on Health, Physical Activity and Disability is worth knowing about. It is funded by CDC's National Center on Birth Defects and Developmental Disabilities, based at the University of Alabama at Birmingham, and it maintains a free directory of programs and resources for people with disabilities and mobility limits. A separate article in this series covers how to compare community classes for accessibility.

The home version, and what counts

The National Institute on Aging sorts activity into four types: endurance, strength, balance, and flexibility. That framing helps indoors, because a rainy day plan built only around walking laps in a hallway quietly drops two of the four. The same institute makes a point worth holding onto: almost anyone, at any age, can do some type of physical activity.

For endurance at home, the options that reliably reach moderate intensity are marching in place, walking laps through whatever loop your home allows, climbing stairs, dancing, stationary cycling if you have a bike, and following a class on television or a screen. Both the federal guidelines and the American Heart Association name dancing outright as an example of aerobic activity, and the heart association also names climbing stairs.

Housework is the honest gray area. Cleaning counts when it is done at a pace that passes the talk test and continues long enough to matter. Fifteen minutes of steady vacuuming or scrubbing can qualify. Folding laundry on the couch does not, no matter how much of it there is. Let the talk test decide rather than the word "chores."

Balance and flexibility work is where an indoor day can quietly outperform an outdoor one, because a kitchen counter and a sturdy chair are right there. The National Institute on Aging lists tai chi among the low impact activities that put less stress on joints. If falls or unsteadiness are already a concern, that is a conversation to have with a health care professional or a physical therapist before you start practicing balance moves alone at home. CDC has a fall prevention program called STEADI, short for Stopping Elderly Accidents, Deaths, and Injuries, that many health care professionals use to screen for fall risk and decide what to recommend.

Strength without a gym

The weekly strength target is the part most people drop first when they cannot leave the house, and it is the easiest to keep. The federal guidelines name push ups alongside lifting weights as an example, which tells you something: body weight counts.

Work backward from CDC's list of major muscle groups. Legs and hips are covered by standing up from a chair and sitting back down under control, and by step ups on a bottom stair. Chest, shoulders, and arms are covered by push ups done against a wall or a kitchen counter, which is the same movement made easier by changing the angle. The back and abdomen respond to movements where you hold a steady position or lift and lower with control. Canned goods, a loaded backpack, or a jug of water can stand in for light weights.

Two cautions keep this useful rather than risky. The number of repetitions, the amount of weight, and how hard to push are individual questions, and a physical therapist or a trained instructor can set them far better than any article. And if you are starting strength work for the first time, if you have heart disease, or if a joint problem limits you, that is a conversation to have first. A separate article in this series covers the questions to ask before starting or changing an exercise routine.

Water, heat, and cold deserve a question first

Indoor pools solve several problems at once. Water exercise appears in the National Institute on Aging's guidance for people managing chronic conditions, and swimming is on its list of low impact activities that are easier on joints. The heart association lists water aerobics among aerobic options. Useful things to ask before you sign up: how warm is the water, is there a lift or a zero entry ramp, are there handrails, and how far is the locker room from the pool deck.

Hot tubs, steam rooms, and saunas are often attached to the same building, and they are not exercise. How your body responds to them, and whether any medicine you take changes that response, is a question for your health care professional or pharmacist rather than something to sort out by trial.

Weather itself is sometimes the health reason to stay in, not just the inconvenience. The American Heart Association notes that people with coronary heart disease often develop angina, meaning chest pain or discomfort, in cold weather, and it advises that some people outdoors in the cold should avoid sudden exertion such as lifting a heavy shovel full of snow. Wind makes cold air behave like colder air: at 30 degrees Fahrenheit with a 30 mile per hour wind, the cooling effect matches 15 degrees. Hypothermia means a body temperature below about 95 degrees Fahrenheit.

Heat cuts the same way. CDC counts adults 65 and older, people with chronic health conditions, and people without air conditioning among those at higher risk of getting sick from heat. Whether any of your medicines affect how you handle hot weather, hot rooms, or heavy sweating is worth asking about directly, because the answer varies by medicine and by person.

Making the indoor switch automatic

Deciding what to do while rain is hitting the window almost never works. Deciding in advance does.

1. 1 Name one default and one place. Not "I will do something inside," but "hallway laps and the stairs, starting in the living room." A default you can picture is a default you will start.
2. 2 Attach it to something already in your day. The end of a phone call, the start of a television program, the minute the dishwasher goes on. Triggers that already happen beat alarms you will silence.
3. 3 Set a low bar for bad days on purpose. Ten minutes is a legitimate target, and the guidelines back you up on that.
4. 4 Count minutes, not workouts. Three 10 minute stretches on a Tuesday is 30 minutes. A week of that is 150.
5. 5 Work around the people you live with. If a downstairs neighbor rules out jumping, walking and strength work are quiet. If you are caring for someone, short sessions during a nap or a show are more realistic than a block of 30 minutes.
6. 6 Keep a second option for the days the first one is blocked. When a shared room is occupied, a chair based routine in a bedroom still counts.

A separate article in this series covers choosing an activity you actually enjoy, and another covers asking someone to be an activity partner. Both apply indoors. Two people on a phone call, each walking laps in their own home, are still exercising together.

Signs to stop, and how indoor days show up in your readings

Stop and get medical attention if you develop chest discomfort or pressure, unusual shortness of breath, dizziness or fainting, or an irregular heartbeat during activity. If a blood pressure reading is 180/120 mm Hg or higher and you have symptoms such as chest pain, shortness of breath, back pain, numbness or weakness, vision change, or difficulty speaking, call 911 rather than waiting to see whether the number comes down. If it is that high with no symptoms, wait at least a minute, take another reading, and contact your health care professional promptly.

If you measure your blood pressure at home, keep activity and measurement apart. Standard technique calls for no exercise, caffeine, or smoking in the 30 minutes before a reading, so a mid morning indoor session and a mid morning reading need space between them.

As for what the activity is doing, the 2025 American Heart Association and American College of Cardiology high blood pressure guideline lists adopting a moderate physical activity program among the lifestyle changes it strongly recommends for preventing or treating elevated blood pressure and high blood pressure. Its lifestyle table estimates that aerobic exercise is associated with systolic pressure, the top number, roughly 4 to 8 mm Hg lower in people with high blood pressure. A 2023 analysis of 270 randomized trials and 15,827 participants reported average reductions of about 4.5 mm Hg for aerobic training, about 6 mm Hg for aerobic and resistance training combined, and about 8 mm Hg for isometric training, the kind where you hold a position under tension. Isometric exercise raises blood pressure while you are doing it and is not right for everyone, so ask your health care professional whether it belongs in your routine before you try it.

None of that is a promise about your own numbers, which depend on many things at once. It is a reason to treat the indoor version of your week as the real thing rather than a placeholder until the weather clears.