My favourite exercise class has got to be Les Mills Body Pump. It’s a barbell class that uses the rep effect so high reps and lower weights to give yourself a full body workout. It includes cardio too!
The classes I go to are 45 minutes or an hour long, the shorter one misses out two tracks so misses two muscle groups (either biceps and triceps or lunges and shoulders) but still gives you a proper workout.
It’s also a great way to start weight training and learn the moves if you’ve never tried it before and want to start!