Sometimes muscles and tendons get injured when a person starts doing an activity before they have warmed up properly. A warm up is a slow increase in the intensity of a physical activity that prepares muscles for an activity. Warming up increases the blood flow to the muscles and increases the heart rate. Warmed-up muscles and tendons are less likely to get injured. For example, before running or playing soccer, a person might jog slowly to warm muscles and increase their heart rate. Even elite athletes need to warm up ( Figure below ).
Jim and Mark both raced in the track event today. Jim got to the field early so he could stretch and do some light jogging before the race. Mark was running late and did not have time to warm up. Besides he reasoned it was best to save his energy for the actual race.
Who's heart rate was lowest at the begining of the race?