I'm exercising five days a week atm. Something along the lines of two or three runs, one of which is a 10k, the other one/two 7-ish; one or two gym sessions - 30 mins cardio then weights and core; and one gentle workout, which is a walk, a yoga class or a Pilates class.
It's not too much as long as it's sustainable and you won't run out of steam or get bored.