Cardio, steps and NHS activity targets for weight loss

Aerobic exercise, the kind that gets you out of breath, protects your heart, lifts your mood and helps keep weight off once it has gone. It does not protect your muscle the way lifting does, which is why the NHS asks for both. Here is what the targets mean and how to reach them from a standing start.

The NHS guidelines in plain English

The UK Chief Medical Officers' guidance, published on the NHS website, asks adults aged 19 to 64 to do:^[1]

• at least 150 minutes of moderate-intensity activity a week, or 75 minutes of vigorous-intensity activity, or a mixture;
• strengthening activities that work all the major muscle groups on at least two days a week;
• activity spread over four or five days, or every day;
• less time sitting or lying down.

The same guidance applies to disabled adults and to people with long-term conditions, adapted to what is possible.^[1] The strength part is covered on the resistance training page; this page is about the rest.

What "moderate" feels like

Moderate activity raises your heart rate, makes you breathe faster and makes you feel warmer. The NHS test is simple: you can still talk, but you could not sing.^[1] Brisk walking, water aerobics, riding a bike on the flat, dancing, doubles tennis, pushing a mower and hiking all count.

Vigorous activity makes you breathe hard and fast; you can only manage a few words at a time. Running, swimming lengths, riding a bike fast or uphill, singles tennis, football and aerobics classes are examples.^[1] One minute of vigorous activity is worth about two of moderate, which is where the 75-minute figure comes from.

If you are carrying a lot of extra weight, brisk walking may already be moderate for you, and that is fine. The intensity is about your body, not the activity.

Steps: how many actually help

Ten thousand steps a day started as a marketing slogan, not a scientific finding. The best evidence comes from a 2022 meta-analysis in The Lancet Public Health that pooled 15 studies of adults wearing step counters, with over 47,000 participants followed for around seven years. The risk of dying from any cause fell steadily as daily steps rose, then flattened: at roughly 6,000 to 8,000 steps a day for people aged 60 and over, and roughly 8,000 to 10,000 for younger adults. Walking faster did not add much once total steps were accounted for.^[2]

Two things follow from that. First, the gains are steepest at the bottom: going from 3,000 to 6,000 steps does more for your health than going from 8,000 to 11,000. Second, a sensible target for most people losing weight is somewhere around 7,000 to 10,000 steps, reached gradually. Step counts do not measure how hard you are working, so they sit alongside the 150-minute target rather than replacing it.

Zone 2, explained simply

"Zone 2" is a term from endurance sport that has spread to fitness apps. It means a steady, comfortable effort you could hold for a long time: breathing noticeably, able to hold a conversation, not gasping. For most people that is a brisk walk, an easy bike ride or a gentle swim. In the NHS language above, it is the lower end of "moderate".

You do not need a heart-rate monitor to find it. If you can talk in full sentences but would rather not, you are there. The value of zone 2 is that it is sustainable: you can do a lot of it without needing days to recover, which matters when you are also lifting and eating less. Harder intervals have their place once you are fit, but they are not where beginners should start.

Why cardio complements lifting rather than replacing it

Aerobic exercise and strength training do different jobs. Cardio improves your heart, lungs, blood pressure and blood sugar control, burns energy and helps with maintaining weight loss. It does much less to keep muscle: the 2025 nutrition advisory notes that aerobic activity alone has a smaller effect on preserving lean mass during rapid weight loss than resistance training or a combination.^[3]

During fast weight loss the priority order is: enough protein, then two or three strength sessions, then as much walking and other cardio as you can recover from. If you are pressed for time, cut cardio before you cut lifting. If you can do both, you get both sets of benefits, and the NHS guidelines ask for both for exactly that reason.^[4]

Starting from zero

If you have not exercised for years, or your weight makes moving uncomfortable, start smaller than feels worthwhile and build slowly.

• Week one: a ten-minute walk on most days. That is it. Wear supportive shoes.
• Weeks two to four: add five minutes a week until you are at 30 minutes, or split it into two 15-minute walks.
• From week five: pick up the pace on part of the walk so that talking becomes harder. Try one longer walk at the weekend.
• Low-impact options if walking hurts your knees or feet: swimming, water aerobics, an exercise bike, a rowing machine, or seated exercise. Water takes the weight off your joints and is often the easiest place to begin.
• Free NHS support: the Better Health "get active" pages include the Couch to 5K running plan, the Active 10 walking app and home workout videos, all free.^[5]

Check with your GP first if you have heart disease, chest pain on exertion, uncontrolled blood pressure or diabetes treated with insulin. Otherwise, the main risk of starting gentle exercise is not starting.

Fast weight loss can leave you with less energy than usual, and a body that is eating far less has less to recover with. If you feel dizzy, unusually exhausted or your resting heart rate is creeping up, ease off and read sleep and recovery and eating when appetite is low.