Budo, it's the amount of aerobic/anaerobic training that you are doing with SanShou and BJJ.
It took me almost 6 months to go from 150 to almost 170lbs (of which I'm sure 1/4 of it is lard) and keep it. And I was just lifting, not grappling. To pack 10lbs of lean meat under your current training conditions, that will be very difficult (not impossible, though.)
If I were you, I'd concentrate on taking BCAAs if I were you. BCAAs up to the wazoo brother. Creatine might help you, but it will also cause water retention.
BCAAs, lots of them, glutamine (5g-10g a day at least), lots of meat, dairy and protein shakes/supplements and a concentration on working your lowerbody first (using the leg press and lunges), back second (via chin ups and heavy dumbbell rows) and the chest (via dumbbell presses.) That's what you'll need to do with the equipment at your dispossal.
I'm not sure if a 5x5 (which is what you were planning to use) will work well with the leg press. It will most likely not work with lunges (as they usually work best with 14-20 steps/reps). For the leg press (with both legs and single leg), a 8-12 rep per set (4-5 sets in total), twice a week, and/or a high intensity, low volume program once a week (* see below) might work for you better to get the fastest possible size gains with your current MA schedule.
Also, if you are doing any cardio outside of MA, don't. Otherwise, you are not going to gain those 10lbs you seek.
- warm up on the leg press and then load the machine with enough that you cannot do more than 12 reps at a time. Without counting the warm up sets, do 3-4 sets.
- follow this up with 2-3 sets of walking lunges, 14-20 steps per set.
- follow up with your favorite chest or back workout and call it a day.
- note: you can do this once or twice a week, depending on your MA workout.
* High Intensity, Low Volume workout: This was one routine I used once that helped gaining a lot. It was way too taxing, though. So use it with care and not more than once a week. If you don't have the discipline to do it only once a week for 3-4 weeks (which I didn't), don't use it. Also, you need to do the normal workout at least once before you do this. A similar thing came up in t-nation a couple of months ago:
- do two warm up sets on the leg press using a moderate weight, and find the amount of weight you can do for no more than 14-15 reps on the leg press. You'll use that load. It doesn't have to be exact, maybe you can do only 12 reps, or you can do 16 reps. That's fine. But always aim at something about 12. If you find you can do more than 15, stop and put a few more pounds. Name this weight X.
- load X weight on the leg press, and crank the reps at 1-1-1 tempo (1 second down, 1 second up, hold the weight for one second, and repeat.) Do the reps until you are close to reach failure. At the top, squeeze your ass as if you were trying to crack a walnut with it. Seriously.
- put the safety on the leg press and take strictly a 20 second break.
- remove the safety and crank the reps again until you get close to failure.
- put the safety on again. Unload about 50% of the weight, and get on the leg press machine.
- Wait a few seconds, remove the safety and crank the reps again, this time to failure.
- Put the safety on, and take 20 seconds break.
- Remove the safety and crank the reps to failure. That is, this is a drop set of 4 individual sets to failure/near failure
Take a 2 minute break and repeat once more (and no more than that!!!!).
Take a recovery drink in between sets.
Once completed do 2-3 sets of walking lunges, 14-20 steps.
Drink a mass gainer protein shake (rich on proteins, carbs and fats) and call it a day with your legs. Follow up with your choice of back or chest exercises (make you always do more back than chest throughout the weekend.)
Take 300-500mg of vitamin C a couple of hours before this. Make sure you take 5-10g of glutamine with lots of BCAAs (either in the protein shake or by themselves) within two hours after the workout. In fact, do this for any workout.
Wait until the next week to repeat this. Make sure you don't have MA training the day immediately after this is done. The day after make sure you take a light walk and move your limbs around to reduce soreness. Keep taking protein supplements and a shitload of BCAAs and good sources of fats.
Do the high intensity/low volume workout once a week for 3-4 weeks. Then take a break from leg training for a week. Then resume with the "normal" workout once or twice a week (or for once or twice before attempting the high intensity/low volume workout again.)