I often hear people joking in class that after the warm-up they’re not sure they have anything left to do a workout. It was also the joke in the early CrossFit days that “our warm-up is your workout”, so today I want to address what is involved in a good warm-up. Implicit in the name, we know that a warm-up should, well, warm us up, but beyond raising our body temperature what does this mean? A good warm-up should raise the body temperature, lube the joints, fire up the nervous system, and get the engines running. Let’s break down each one.
Raising the body temperature can be as easy as going for a jog, getting 30 jumping jacks, 10 burpees etc. This one can really be anything that will raise the heart rate and since it’s one of the first things you’ll be doing when you enter the gym we want to keep it simple. Performing some squat snatches would raise the temperature as well but since that’s a very technical lift I wouldn’t suggest starting there. Keep it simple here and just move around.
Your joints are naturally lubricated by synovial fluid. This is a milky white substance that allows the joint to slide and glide properly with minimum friction. As we move we actually increase the synovial fluid available in our joints. Movement also brings in fresh blood flow carrying nutrients and oxygen, all of which help to provide an environment conducive to more movement. This is one reason why a joint can feel stiff when we first try to move it but then feel much more mobile after some movement. Our warm-up should specifically address the joints that we plan on targeting in the workout, but more generally address all of our joints because for most this is the only hour in the day they actually get to move around, so let’s make the most of it.
The warm-up should also prepare the Central Nervous System (CNS) for activity. This impacts our ability to recruit muscle fibers to the extent and magnitude that will be demanded of them in the workout. For instance, warming up for a 5k run requires a much different type of muscle recruitment than a workout consisting of explosive movements such as box jumps. The warm-up for each should reflect this difference. This step is crucial for those who have been sitting sedentary or even sleeping for the previous several hours.
Lastly, we need to prime our engines. The body has three energy pathways, or engines, it relies on for activity: the phosphagen, the glycolytic, and the oxidative or aerobic. The energy system used is determined by the magnitude and duration of the activity, but to some extent all of them are utilized. The phosphagen is for short all-out burst of energy, the glycolytic for moderate outputs of up to several minutes, and then the oxidative for lower intensity in excess of several minutes. If your heart rate during a 3 minute high intensity workout is 180 bpm, but your warm-up only ever gets you up to 120 bpm, you can probably imagine that there will be some big shifts happening during that 60 bpm swing. A proper warm-up will already have run your body through that spectrum so the changes are more subtle and our bodies already semi-adapted and more efficient at making the transitions. You can experience this for yourself by trying to run a 400m sprint cold vs. properly warmed up.
This last part is important and often overlooked. There is this false notion that pushing oneself in a warm-up will detract from ones abilities in the actual workout. It’s as if we view our bodies abilities at movements at having an account’s worth of said movement and once we use them up we’re out. Fortunately, that’s not how the body works. While a warm-up can go too far it is important that all of our energy systems be accessed so the transitions in the workout are smoother and less taxing. In our warm-up we need to tap into these systems slightly to bring them on board but we don’t want to spend too much time there which can fatigue us for the work ahead.
There you have it, all the components of a good warm-up. Get your heart rate up, move your joints, specifically the ones you’ll be using in the workout, perform exercises that will allow your CNS to practice similar muscle contractions in those same muscle-groups you’ll later be using. Finally, be sure you warm-up your engines appropriately so when it’s go time you don’t miss a gear!