To strengthen your legs I wouldn’t train cardio and legs together, sure a slow 5 minute jog followed by stretches will act as a good warm up, but don’t be doing a 20 minute plus sprint session followed by a strengthening leg session.
Adding squats into a sprint session (such as arnys hill sprint session) is there to increase the endurance in your legs which is something you absolutely need. A lot of people get strength and endurance confused.
To increase strength you need to be squatting a moderate to heavy weight, obviously start off towards the moderate end of the scale. I’ll write down a training plan which I’m currently using to increase strength, and it based on 1 lower body session per week.
Week 1 - 3 X 5
Week 2 - 2 X 3
Week 3 - 2 X 2
Week 4 - 1 X 3 (This is a 3 rep max. test)
Week 5 (Deload week) - 5 X 5
Week (1) 6 - Start the 5 week cycle again based on your week 4 three rep max. test.
I’ll explain in detail. Week 1 you will choose a weight which you perceive is heavy but you can get 5 - 7 reps out. You’ll Squat this for 3 sets of 5.
The second week the reps come down by 2 (number of reps correlates to weight - lower reps the heavier the weight) and the sets come down by 1. For this jump down, squat for one set only the weight you did in week 1 and add 2.5 - 5kg until you getting around the 3 - 4 rep range. Then squat this weight for 2 X 3.
Week 3 same principle again.
Week 4, by this time you would have made strength gains and your going to test your 3 rep max. Squat for 3 reps, add weight, squat for 3 reps, add weight and repeat until you’ve found your 3 rep max.
Week 5 is a deload week and you’ll squat a lighter weight for 5 X 5.
Week 6 you start back at week 1 and start the 5 week cycle again. Your week 1 3 X 5 reps will be slightly lighter than your last 3 rep max. test.
Is a weighted vest advised on hill sprints passed this point? Aware weighted runs are discouraged until RT but the nature of the hill sprint takes away a lot of the impact through the leg so a weighted hill sprint might not be as dangerous.
In deference to hill sprints with a weighted vest, DO NOT wear it to come down. Walking down hill without anything is already damaging to back, knees and ankles (in a small way) so avoid extra issues by walking downhill with weight.