Larry “Molson†Olsen
On a Sunny Sunday on August 8, 2004, Larry Olsen had one of the best races of his career as a racecar driver. Competing in the EP class, and seated in 9th, with three other riders in front. Larry worked his way through the pack to finish in first place, with an average lap time under 1 minute 45 seconds.
Heart Rate Data:
Pre-Race
5 minutes pre race warning the watch was started. Heart rate was approximately 110-120 beats per minute for the first 3 minutes of pre race, and showed a slight increase of about 10 beats per minutes from minute 3 to minute four. At this point the engines were started, and at 3: 55 seconds the car and driver were released to the track. The driver settled into a heart rate of around 130-135 minutes from minute 4 to minute 5, and during the pre positioning lap averaged in the low 140’s for a heart rate until the green flag at minute 8:08.
Green Flag
Over the first 30 seconds of the race the heart rate increased from 143 to 166 beats per minute leveling off during the first lap. 20 – 25 seconds into the second lap there was a slight decrease from the 167-168 range to the 163-164 range for about 15 seconds. This was to be the lowest heart rate recorded for the race.
Heart rates remained in the low 170’s throughout the remaining second and third laps. At about 35 seconds from the end of the forth lap the heart rate increased into the mid 170’s for one full minute, and dropped back into the low 170’s to upper 160’s from lap 5 to lap 8. Halfway through lap number 8 and into lap number 9, the heart rate increased 8-9 beats for one full minute before returning back into to the low 170’s.
Heart rates remained in the 169-175 range from the rest of lap 9 through lap 12.  At the start of lap 12 the heart rate increased from 169 to 185, a 16 beat difference for over 20 seconds.  This was the largest variation and highest obtained heart rate during the race, 185 beats per minute.  Heart rates for the remainder of the race stayed in a relatively narrow range, from 166 to 173 beats per minute.
Post Race
Nearly 45 seconds after crossing the finish line, the heart rates dropped quickly into the low 150’s. At approximately 4 minutes after the race completion, the heart rates increased back into the upper 170’s into the 180’s over the next few minutes. At seven minutes after race completion the heart rates dropped suddenly reaching as low as 134 beats per minute 20 seconds before the watch was turned off.
Impressions:
Typically, increased in heart rate are commensurate with increases in workload. Since the muscular work, defined as force times distance, is not the largest variable in auto racing the impact to the cardiac system is quite apparent. High heart rates with low oxygen consumption demands indicate a large amount of shunting of blood to the surface of the skin to aid in cooling the body. With the decrease in the blood supply in central circulation, a noted rise in heart rates is noted. The elevated heart rates seen during the race are further accentuated from the response of the sympathetic nervous system to the performance in racing competition.
It was interesting to note that in the qualifying round earlier in the day, the heart rate response average was 10-15 beats less then during the actual race. This was most probably due to the increased “pressure†to perform when the increased effort was warranted.
Fluid Loss Pre Race:
Fluid loss during the qualifying race was predicted very accurately using the Acumen Hydro-Alert watch system. Actual losses were estimated at 17.6 ounces in the 15 minute qualifying race. Predicted losses were estimated at 16 ounces on the watch. Fluid loss was not measured in the sweat contained in the underwear of the driver, estimated at approximately one ounce, and another 2-3 ounces were lost in the approximate 5 to 8 minutes that the driver took to get dressed, and get his vehicle to the staging area.
Summary: -1.0 ounces lost in sweat contained in underwear of driver
                                    – 2.5      ounces in time to get dressed and get to staging area.
+17.6 ounces lost on scale
                                    +17.6  ounces lost on scale
14.1 ounces lost during the pre race, race and 5 min post race
16.0 ounces recorded in fluid loss with hydro-alert system.
Most expert recommendation state that fluid replacement should exceed the weight lost on the scale by as much as 25%. A near optimal rate of fluid replacement of 113% of what was lost on the scale was reported.
Fluid Loss Race Competition:
Fluid loss during the race competition was predicted very accurately using the Acumen Hydro-Alert watch system. Actual losses were estimated at 46.1 ounces in the 30 minute qualifying race. Predicted losses were estimated at 46.4 ounces on the watch. Fluid loss was not measured in the sweat contained in the underwear of the driver, estimated at approximately one ounce, and another 5-6 ounces were lost in the approximate 15 to 20 minutes that the driver took to get dressed, and wait with his vehicle to the staging area. Temperature in the afternoon race was approximately 90 degrees on the track with 50% humidity.
Summary: -1.0 ounces lost in sweat contained in underwear of driver
                                    – 5.5      ounces in time to get dressed and get to staging area.
                                    +46.4  ounces lost on scale.
39.9 ounces lost during the pre race, and 5 min post race.
46.1 ounces recorded in fluid loss with hydro-alert system.
Most expert recommendation state that fluid replacement should exceed the weight lost on the scale by as much as 25%. A near optimal rate of fluid replacement of 116% of what was lost on the scale was reported.
Recommendation:
The hydro-alert watch would be a valuable system to maintain fluid balance during auto racing especially in longer races, on hot humid days.