I've made a mental note of warming up before each and every weight training session. Honestly, warming up is so boring and doesn't look manly-man but it's nonetheless very important.
My lack of warm-up (actually I didn't do any warm-up on that dreadful day) was one of the reasons of how I sustained my shoulder injury.
Warm up prepares your body for an exercise or workout. During warm up, your circulatory system gradually pumps oxygen-rich blood to your working muscles to "warm it up". Once you have adequately warmed up, your body will be ready for an increase in workout intensity. Since your muscles are warmed up, they will be able to better absorb shocks and impacts during the course of your exercise or workout, thus reducing the chance of sustaining an injury.
Benefits of warming up are as follows:-
1. Increases blood flow to muscle tissues, making the muscles more flexible and elastic;
2. Increases delivery of O2 and nutrients to your working muscles;
3. Prepares your working muscles for workout;
4. Prepares your hearth for an increase in workload and prevents a rapid increase in blood pressure;
5. Prepares your mind for workout;
6. Prepares your nerve-to-muscle system for workout;
7. Improves muscles coordination and reaction;
8. Reduces the chance of sustaining an injury.
I would usually start my warm up by doing 40-50 burpees, followed by some basic stretching movements. I find that doing burpees is the most efficient and effective way of starting the engine and breaking a sweat. Thereafter, I would do 2 warm-up sets prior to doing the actual working sets for each movement.
I guess I've to accept that I'm getting older by the day and thus cannot be too careful :-P