How do you vary types of exercise throughout the week?

[DoloresGove]

I'm hoping to run twice a week, spin once a week and add some weights/upper body resistance once a week too.

Would this sort of "regime" be OK? I remember hearing that doing any sort of exercise just once a week wasn't worth it as you weren't doing it frequently enough for it to make a difference... or is that if you're only exercising literally once a week?

I think the best thing you can do for your body is weight training. You could mix it up with cardio and do circuit training? I think you should do weights at least three times a week for it to make any difference and don't be afraid of lifting heavy.

I weight train 3x a week and now do v little cardio. I'll do hiit training or a run once a week just because I like it and it's good for cardio vascular health but it's the weight training that has made the difference to my body shape.

To increase cardiovascular fitness you'll probably need to exercise at least twice a week, but you can use different methods. Cycle, run crosstrainer etc.

To increase lean body mass you'll probably need to strength train at least twice per week.

That's a very broad overview.