Do you want a quick workout that will work your whole body? We know swimming works the whole body however if you don't have the time or the inclination to swim these 4 exercises will give you an all over workout.
1. Squats - ideally "ass to grass" however this depth should be developed over time as it requires a lot of ankle flexibility that most people are lacking. If technique is poor and you round your lower back to compensate, this can cause back injuries so only go as low as you can maintaining optimal technique.
3. Push ups - as above it is really important to learn to lock your shoulder blades down to stabilise your shoulder when performing these. Start performing push ups with your hands on a kitchen bench height then find lower stable objects to increase the degree of difficulty.
Giving you my honest opinion on all things health related. Keeping it real and from the heart.