You can join a gym whatever your level of fitness – the important thing is to set yourself goals that are suitable for you. If you are very unfit, you will need to start off with gentle exercises and build up slowly from there. You may want to hire a personal trainer to create an exercise routine for you.
If you want to focus on strength, then you will probably use weights, either in the form of machines or free weights. People usually lift weights in sets of perhaps 10 or 20, resting between sets. When you use the machines, you will need to adjust them to suit you, for example by raising or lowering the seat, and choosing how much weight you want to lift. If you sweat a lot, don’t forget to wipe down the equipment after you’ve used it.
People often go to the gym in order to lose weight. Many machines such as treadmills (running machines) show the number of calories you have used during your exercise session, and the more intense the workout, the more calories you will burn. This can help to motivate you (make you want to work harder), though it may have the opposite effect, since the amount of running needed to burn off a slice of cake is a lot more than most people realise!
Many gyms offer a range of classes. Aerobics can help you to work all the major muscle groups. High-impact classes involve a lot of jumping, while low-impact classes avoid sudden, hard movements that might hurt your knees or back. Yoga helps to improve flexibility (the amount you can bend and stretch), and pilates focuses on strengthening the core muscles in your tummy.
Your body gets used to exercises, so it’s good to vary your programme from time to time. It’s important to warm up before you exercise because this helps to prevent injury, and it’s a good idea to cool down at the end too, rather than simply stopping. However, if your muscles don’t ache a bit afterwards, you probably haven’t worked hard enough!