Completing a warm up before your session is vital, and something that not many of us do, often, due to the reduced time which they have.
By just increasing your session time by 10 minutes in order to complete a warm up could benefit your session greatly which could result in you being able to lift heavier and ultimately feel better,
Your warm up could include a steady walk or jog on a treadmill, going on the bikes or even the rower. Doing this for just 10 minutes will allow your blood to circulate around your body more, which will provide the working muscles with more oxygen giving them more energy to perform exercises, alongside increasing the elasticity within them which will decrease your risk of suffering from an injury.
Not only does a warm up physically enable you to be more prepared for your session, it also allows you to prepare mentally, giving you time to think about what you are planning on doing in the session and allows you to focus- which will obviously increase your progress and enable you to work at a greater effort.
Stretching should also be included within your session as this will further increase the elasticity in your muscles, especially when you focus on stretching the areas which you are planning on using. This should include a range of static and dynamic to optimise the stretch of the muscles.