The body is a complex machine and a whole series of complicated actions and reactions begin when you start to exercise. I have set a few out below*.
You may wonder why it is important to consider warm ups at all. Regardless of your ability, level or sport, preparing your body for the effort it is about to make is vital to ensure that you’re able to put in your best performance. Being aware of how the body reacts to race pace effort is instructive. You should warm up for training sessions as well as races although in training the warm up can be part of the session and should be if it is an interval workout.
The primary objective of any warm up is to prepare your body for the stresses that it will be subjected to in the effort that’s about to begin. A warm body is more ready for the effort, and less likely to get injured. As described above, your body is undergoing complex metabolic processes, and the goal of a good warm-up is to warn the body to get ready for the effort involved and get those processes moving.
When racing to suddenly go from standing still to trying to go at race pace particularly in short intense races, is to suddenly overload those systems and cause the body to have to try to catch up with itself. That is likely to involve shortness of breath and faster, shallower breathing, In swimming or Triathlon you are of course already restricting and trying to control your breathing so that’s the last thing you need. To go as hard as possible on cold muscles and ligaments is to risk injury.
The sudden increase in activity, a struggle to get enough oxygen in and the adrenaline of a race start can push you into an anaerobic state, and if the body is struggling to catch up with everything going on you will stay that way for longer. The overall effect is more likely to result in a panic in an open water event.
An effective warm up reduces that effect because your body will have the ability to more quickly deliver glycogen and oxygen to struggling muscles, lungs and circulatory systems are “warmed up” delivering more blood to muscles and carrying away waste products and the hormones associated with exercise have been released into the system. The process of providing extra glycogen from the body’s stores will be triggered.
How much should I do? The answer will depend on the length of the event and the intensity of the effort. High intensity sprint races will require a longer warm up possibly of 15 minutes starting at a low intensity but building towards the level of effort you intend to work at in the race, or if it’s a short training run, simply running slower for the first mile and increasing speed as you go, will suffice. Mimicking the sport in your warm is also advantageous… Swimming easy efforts then faster efforts if you are doing an open water swim for instance… Just for a few minutes if time is tight, will help get your aerobic system fired up for the efforts to come.
If warming up for a Long Distance race you are likely to be working at aerobic pace anyway so a shorter more gentle warm up will suffice. Try to finish the warm up as close to the start as possible although the race start format may well dictate timings. Remember the goal is not to wear yourself out but to prepare you for what’s to come.
Take advantage of the opportunity to swim before the start if offered by the organiser (and if they don’t why not?) and take the opportunity to acclimatise to the water, dip your face in, take it out and repeat several times to try to avoid an “Ice Cream Headache”. If you can’t get in the water don’t just wave your arms about vaguely, jog around to get the blood flowing, mimic the swimming stroke in warming arms up, do dynamic stretches and move head and neck.
*As the Muscles demand more fuel – principally Oxygen and Glycogen (produced from the body’s stores initially) – Arteries and veins will constrict or dilate, rapidly redistributing blood flow to meet the demands of exercise. During exercise, the arteries dilate in the principal working muscles and blood flow increases through the smallest vessels (capillaries), which were previously closed. The increased flow of blood to the muscles increases the exchanges of oxygen, the release of heat and the metabolisation of lactate (also called Lactic acid) and removal of carbon dioxide.
The body will begin to convert Lactate to glycogen in the Liver to make it available to the muscles.
The nervous system prepares the body for exercise by secreting hormones signaling dilation of the blood vessels in the heart and working muscles, and secretion of hormones in inactive tissue to constrict those blood vessels. With training, these systems act more efficiently and rapidly to redistribute blood.
Blood redistribution can take several minutes; starting exercise abruptly doesn’t allow these changes to occur smoothly. An abrupt start can leave you breathless and strain unprepared muscles.