What I do is 5/3/1 program by Jim Wendler. Alright, this is going to be a bit long Also, you can find lots of Wendler's stuff online, and if you can, you should buy the e-book (it's like $20 and a quick read).
So, the idea is that we want to continually progress, but want to do so without beating the crap out of ourselves. The program runs in cycles, with the intention of increasing the weight each cycle.
Here's how it works:
The main lifts are the press, deadlift, bench press, and squat.
Start by finding your 1 rep max (either by doing it or using a rep max calculator) for each of those lifts. You then take 90% of that 1RM to calculate all of your lifts. So, if your 1 RM squat is 200 lbs, you use 180 lbs as your basis for calculating things in your first cycle. The reason you want to start with 90% of your 1 RM is that it leaves room to grow, and will allow your first cycle to start out strong.
The reason the program is called 5/3/1 is because each week the rep scheme changes (as well as the weight on the bar). The first week is your 5 rep week, second week is 3 rep week, and the last week is a 1 rep week. Each week the weight goes up based on a % of that '90% 1 RM' that you are starting with.
Week one
65%x5, 75%x5, 85%x5+
Week two
70%x3, 80%x3, 90%x3+
Week three
75%x5, 85%x3, 95%x1+
Week four (deload)
40%x5, 50%x5, 60%x5
The '+' means get at least the required number of reps, but see how many you can get with good form and technique. You don't have to do it, but it's good to try and set rep records as well as weight records.
After you finish one cycle (at four sessions per week, one cycle should take one month), you add weight to the '90% of 1 RM' that you use to calculate your weights. Add 5 pounds to upper body movements, and 10 pounds to lower body movements. So, if you were using 180 pounds as your '90% 1 RM' for the squat, cycle two would use 190 pounds to calculate your weights.
Just as an example, using 180 pounds for your first cycle would be this:
Week 1
117x5, 135x5, 153x5+
Week 2
126x3, 144x3, 162x3+
Week 3
135x5, 153x3, 171x1+
Week 4
72x5, 90x5, 108x5
And then cycle two would use 190, so this is how it would go:
Week 1
123x5, 142x5, 161x5+
Week 2
133x3, 152x3, 171x3+
Week 3
142x5, 161x3, 180x1+
Week 4
76x5, 95x5, 114x5
Having a deload week in there is nice both for physical recovery and for mental recovery.
Again, google it, you'll find better explanations than mine There's also a free calculator out there if you google 'black iron beast 5/3/1 calculator'. what do you think? I'm tweaking this to fit a mid distance running schedule. I am an extremely injury prone runner. I have decided to lift more and focus on quality running training and a lot of cycling/swimming to help out in the entail first couple of months. Any feed back?