Strength training for older adults: why twice a week

Walking is the form of exercise most people think of first, and it is a good one. Yet the major guidelines for older adults ask for something more: muscle-strengthening activity on at least 2 days a week. This note explains what that means, why the agencies recommend it, how people usually begin, and where the evidence is thinner than the advice sounds.

What the guidelines ask for

The CDC says adults aged 65 and older need, every week, 150 minutes of moderate aerobic activity (or 75 vigorous, or a mix), at least 2 days of activities that strengthen muscles, and activities that improve balance. The NHS says the same for adults over 65: strength, balance and flexibility activities on at least 2 days a week, on top of the aerobic minutes. The WHO adds a line worth remembering: muscle strengthening benefits everyone.

The NHS is explicit that strengthening is a separate job. Muscle-strengthening exercises are not always aerobic, it says, so they need to be done in addition to the 150 minutes. Our note on walking and how much is enough covers the aerobic half.

Why strengthening gets its own slot

The National Institute on Aging (NIA) explains the reasoning in everyday terms. Muscle-strengthening improves physical function and can make daily tasks easier, such as getting up from a chair, climbing stairs and carrying groceries. It is also key to maintaining existing strength, slowing the loss of muscle mass and helping to prevent falls and fall-related injuries.

A caution belongs here. The strongest evidence we found on falls comes from a Cochrane review of 108 trials, and it found high-certainty benefit mainly for programmes built around balance and functional exercises. For programmes that were mostly resistance training on its own, the reviewers said they were uncertain of the effect on falls. Strengthening makes sense for function and independence, but it is not a stand-alone fall-prevention plan. We look at that review in balance and falls prevention.

Starting gently

The NIA suggests that beginners try exercises without weights or resistance bands until they are comfortable with the movements. Body-weight moves, such as leg raises, squats or arm circles, are among its examples. Household effort counts too: carrying heavy shopping and gardening that involves digging and lifting both appear on the lists from the NIA and NHS.

How hard and how often? The CDC says to work the muscles until it is hard to do another repetition without help, aiming for 8 to 12 repetitions of an activity (one set), and at least one set. Two or three sets bring more benefit. The NIA suggests working all the major muscle groups (legs, hips, back, abdomen, chest, shoulders and arms), while avoiding the same muscle group on two days in a row so it can recover. The NHS says to work to the point where you need a short rest before repeating.

The NIA also says to build up over weeks to months, and to go back gradually after a break such as illness or travel. Warm up first, for example by using lighter weights. Breathe out during the effort and in as you relax, do not hold your breath, and avoid locking arm or leg joints straight.

What an older adult might expect

Honest answer: the pages we read do not promise a timetable. The NIA says gradual increases in weight, repetitions or days per week result in stronger muscles, and that overdoing it can cause exhaustion, sore joints and muscle pain or injury. The NIA's own advice is to listen to your body, and to seek guidance if you are unsure about a movement.

Technique matters. The NIA suggests booking a session or two with a personal trainer, or finding a group class at a gym, recreation centre or senior centre, to learn proper form. It also points to free online videos. Group classes bring company as well as instruction, and the NIA notes that social support helps people stick with a routine. See social connection and wellbeing for more on that.

When to ask a clinician

The NHS advises speaking to a GP first if you have not exercised for some time or have medical conditions or concerns. The NIA is more relaxed for people without an existing injury or chronic condition who increase gradually, but says anyone unsure about a particular movement should seek guidance from a doctor or physical therapist. If you have a chronic condition, it advises talking with your doctor about what you can do. Your own clinician has the final word, and this note is background reading, not a programme for any one person. More on this theme sits on the movement shelf.

The short version

Strengthening activity on at least 2 days a week is the shared advice from the CDC, NHS and NIA, mainly because it supports everyday function and independence. Start light, build slowly, and treat evidence for falls with care. If you have health conditions or are unsure of a movement, ask a clinician or physical therapist before you begin.