To me, it definitely depends on training goals. I always recommend at least a 5-10 minute warm up of some type of aerobic activity before strength training for everyone – regardless of goals & training levels. I don’t see a problem with doing 20-25 minutes of cardio before moderate strength training – in fact, I encourage it. They might as well extend the warm up another 10-15 minutes and knock it out. However, if gaining strength & muscle mass is the primary goal, I would suggest doing the cardio workout after hitting the weights and/or during off days. That way, you won’t be too fatigued when training with heavier weights.