Training with a broken collarbone

This is currently week 2 into my broken collarbone recovery, and even though I did a little bit of exercise last week already, this week it felt a little bit more safe to do some more work.
After a check-up at the end of last week, my doctor told me that the bone usually starts to grow again in the 2nd week, so it's advised to NOT do anything too strenuous just yet. Learn to accept that this is just how it is, and taking a rest is not going to kill you.

What I noticed, is that even if you're using one side of your shoulders, when you tense up to pull, pick something up, etc., it does effect the injured side as well. Everything is connected, so take it easy. Especially in the first 4 weeks, you are not allowed to raise your arm above 70 degrees.

The exercises you can do, are basically just legs and core. After looking around a bit online, I found a few things to do that can help keep you in shape, and also get your heart rate up.

Legs - Bodyweight

Bulgarian squats
These are very good in the beginning, because you can keep your arm in the sling more comfortably.
Make sure you have something near you to stabilize yourself.
Wall sits
Keep these going as long as possible, it will guaranteed burn your quads.
(Walking) Lunges
You can do them in both variations, the walking lunge is a bit more comfortable if you're able to go without the sling.
Air squats
I found them the best to do with the injured arm hanging down my side, and my good arm up for some balance. (squat holds are great too)
(Half) Pistols
Unfortunately I can't do full pistols yet, but half-pistols work really well, just careful with putting tension on the injured shoulder when you go forward.

Legs - In the gym

Leg press
Perfect for building strength, since it simulates a squat.
Leg Extensions
This is nice for building muscle endurance, when you go for high reps.

Core

Hollow Holds
If you have a good crossfit coach, you were doing these already anyway, so this is a perfect opportunity to get REALLY good at them. Instead of reaching your arms out, keep them next to you.
Supermans
Great for getting a stronger back and glutes. Also keep you arms along your torso.

For cardio, you could ride the stationary bike or even use the stair master. If you do 250 air squats for time, you can count on breaking a sweat and getting your heart rate up as well.

4 Work-out examples

100 Bulgarian squats (50L/50R)
5 x 30 sec Hollow hold
100 Walking lunges
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250 Air Squats
6 x 30 sec Hollow hold
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4 x 12 Leg Press
4 x 12 Leg Extension
5 x 30 sec Hollow holds
5 x 30 sec Supermans
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3 rounds:
10 pistols each leg
1 min Hollow hold
50 squats

Finally

Before you start all this, check with your doctor or physiotherapist. If you put too much strain on your injury too soon, this might end up worse, so be smart!
Tip: kinesio tape on the bent elbow and on the injured shoulder works wonders for the bloodflow and stiffness.

For more info on recovery, like doing the pendulum exercise, check here.
For my nutrition plan to help speed recovery, go here, and for week 3, go here.