I remember 15 1/2 years ago I decided to get into shape. I started going to the gym and running 2 miles as a warm-up. I would then do light resistance training on machines. Doing that, along with watching my diet, I was able to get into really good shape.
The biggest problem I had? I had no plan. I would go to the gym, walk the track for two laps to warm up, run 28 laps (which equaled two miles) and then walk two more laps to cool down. Then I would hit the electronic machines randomly. I didn't have goals. I didn't have any overriding thing I was trying to accomplish.
Granted I did see changes, and people complimented me on conditioning, but I couldn't lift any more weight than I ever had. My stamina increased in playing pick-up sports, but really I was just flailing along without any real clear path to where I wanted to be.
I don't even remember when or why I stopped. It just kind of happened. And there is no surprise to that since I wasn't even consistent in the nights of the week I worked out!
That is what I love about the Strong Lifts 5x5 program. It gives you plan. Mehdi encourages you to have goals. The overall thing you are trying to accomplish is to become stronger. It is 3 days a week (NEVER two days in a row), an hour to an hour and a half each time. And the plan is so simple. Squats, bench press, barbell rows one workout. Squats, overhead press, deadlifts the next. And continue to rotate those. Adding 5 pounds to each lift each time you do it.
I still watch, while I rest between sets, other lifters at the gym wandering around aimlessly. Doing dumbbell curls for a random number of reps, at a randomly grabbed weight, and then floundering on to their next exercise. No plan. And therefore no consistency.
That will never be me. Ever again.