Great question. I usually do not do any warm up exercises immediately before jumping in the pool or on my bike, but that is me, you should certainly try warm up exercises if you want to. When I begin a bike workout, I usually cycle at a moderate pace for about 10-15 minutes before I get into my main workout. I also cooldown in a similar fashion. When I begin a swim workout, I usually swim about about 300 yds of freestyle at a moderate pace followed by 5-10 minutes of nonfree, kicking, and drills before getting into my main workout. Other exercises I do outside the pool or off the bike include free weight squats, abs, shoulder exercises utilizing dumbbells, yoga stretching, and some weight training. If you're looking for pre-swim and bike warm ups, you might want to try a light yoga workout, a light set of free weight squats, or exercises utilizing resistance tube. This also depends on what distance you're training for. I'm training for olympic and half-iron races. If you're training for a full IM, then you might want to follow something different.