I do hiit running once or twice a week, stationary bike interval training, elliptical and outdoor cycling along with some general body weight exercises.

I just do walking on the treadmill quite fast paced 30-45mins on the days I don't lift.

if you want to add some assistance work, you can add dips, chins, or ab work to the end of your routine. Its not really necessary though, and in a few weeks almost everyone says they don't have the energy left to do anything else.

Those are medhi's recommendations anyway. For me personally I'd recommend dips over anything else, the genuine kind on a dip station (I use a machine with assistance but you could also use a band to assist) as Nick and I both credit those with some seriously rocketing bench press strength and they hit the core pretty well too (unless you put so much assistance on there that you don't have to work for it, so don't do that). Chin ups are also pretty good, but we've both just felt like dips are slightly more helpful.

I probably wouldn't add leg work, but the other thing we've found useful are 1 arm rows although really, at the end of SL you mostly are so tired that you don't have a lot of GO time for anything else. You could do farmers walks instead - basically I'm looking at these as grip strength training more than anything. I would ...hrm. I dunno. The rows are kinda strenuous done properly, you won't have juice left for them. I'd probably do the farmers walks.

so like. ..I'd probably do dips on DL day and then farmers walks on the other day.

I personally just do some light jogging (and short, 20 minutes) 2-3x a week

I'm triathlon training. so I take formal swimming lessons once a week and try to practice strokes and breathing on my non-SL days. on those days I also alternate C25K and cycling. I'm honestly having trouble fitting it all in. I like lifting but it's taking over my training and my #1 goal is the Tri.