My schedule and regimen is different than most people's, but I do my long run on Sunday and treat it like workout, usually start easy and progress until I'm running a decent pace by 2/3 of the way through. Then I lift weights on Monday with no running to give my joints a rest. Workout like a threshold type run on Thursdays. Other days are easy. I'm in my 30s and am training for all around health and fitness at this point though. Do what works for you.