What the minimum actually is
The World Health Organization recommends muscle-strengthening work that hits all the major muscle groups on two or more days a week, on top of 150–300 minutes of moderate aerobic activity.1 Two lifting sessions is the floor. Four gives you room to lose one to a bad week and still clear it.
Put the sessions in the diary before the week starts
Monday, Wednesday, Friday, Saturday. Time and place, written down. If-then plans like this — when and where, decided in advance — have a medium-to-large effect on whether people follow through.2
Build the fallback in
Decide now what happens when a day goes wrong: 'If I miss Wednesday, I train Thursday at 7am.' A plan with a fallback survives a bad week. A plan without one dies on the first.
Make each session short enough to keep
- Forty-five minutes is enough.
- Big lifts first — a squat or deadlift, a press, a row.
- Log the top set, then leave.
Move the rest of the day too
The same WHO guidelines say to limit time spent sitting, and that swapping it for activity of any intensity — light included — has health benefits.1 A desk job is eight hours of sitting. Walk the phone calls.
Give it longer than a month
In the best-known study of habit formation, it took a median of 66 days for a daily behaviour to become automatic, and anywhere from 18 to 254.3 Four sessions a week becomes the default somewhere past the second month. Until then, it needs checking.