heavier weights are great, but not entirely necessary. some of the strongest, fittest people on this forum haven't been to a gym in a while (about 2 years for me). programs like simplefit take 20 minutes max 3 times per week, and even 5-10 minutes of slow cadence body weight exercises will make you feel like you've spent hours in the gym. try this...hold your 32 pounder up on your shoulders or in front of you, and do some really slow squats (4-5 seconds down, 4-5 seconds up). your legs will be screaming in no time.
You are there is lots of sprinting in soccer - Lift heavy and enjoy it.
Eating primal is not a diet, it is a way of life.
Don't forget to play!