Cardio is great for you if endurance and just all around feeling better is your goals, and losing weight of course for most people. Great back workout yesterday, going to hit legs today might even do a quad/hamstring split this week. Meaning today I'd focus primarily on my quadriceps and another day this week focus on my hamstrings.

today all presses/squats will be done with a closer stance than on normal leg days to hit the quads little better.

Front Squats/5 sets/8-12
Leg Press/4 sets/8-15
Barbell Lunge/3 sets/10
Hack Squats/4 sets/10-12
Quad Ext/3 sets/failure

"You wanna be big lift big weights, if you want to be small then lift small weights"