I'm trying to mix up my workouts every few weeks now and started with 6 sets of front squats starting on 60 kgs and increasing by 20 kg each set until i reached 120 kgs.
Front squats are a lot harder than normal squats mainly due to the difficulty of holding the bar in place, its either on your throat a little which makes breathing difficult or its lower and your fighting to hold the bar in position as it try's to roll down your chest.
Below is a video of normal squats - 160 kgs for 7 reps which I'm currently doing at the gym located at our Brittany holiday cottage
Front squats tend to put more focus on your quadriceps and I hope will build a better outer sweep.
After the squats it was 5 sets of leg extensions, 4 sets of leg curls and 4 sets of standing calf raises.
The health club / fitness center is available for our guest staying in La Forge and La Veille maison