came in seventeen of twenty-one times. In the fourth week complete
recovery of the original pulse rate within twenty-eight minutes
occurred in every one of the twenty-one tests.

Another way of noting improved condition in conjunction with
fatigue production is the increasing number of quicker recoveries.
In the first and second weeks there were no complete recoveries
of the original pulse rates within two minutes. In the third week
there were eight recoveries within the first two minutes of rest
after the completion of twenty-one curves. In the third week there
were nine trials of the twenty-one, in which there was a recovery
of the original pulse rate with the first two minutes of rest. In the
first week there were only four recoveries in twenty-eight minutes.
In the second week there were nine recoveries within eight minutes
rest. The third week showed ten recoveries within four minutes.
The fourth week showed twelve recoveries within four minutes rest.

Production, recovery, and improvement varied within the same
person with improved training, condition, and application. Pro-
duction and recovery vary with foods, rest, sunshine, heat, and
other fundamentals of physical and functional fitness. Production
and recovery vary with thoughts, with surroundings, and with
association.

6. Aircrew Series—Leg Muscles

Four hundred Aircrew Students worked in nearly 6000 fatigue
curves on successive days. The fatigue and condition curves fol-
lowed the regularly established patterns. In addition to spot run-
ning, the curves were made with two other similar skills of right
and left arm jabbing and flexion-extension at the hips. The in-
hibitions of fatigue were apparent either in good or bad condition.
The improved Production through ten days training is graphically
shown in Figure 13. The improved condition is shown through
quicker recovery and slower pulse rates in Figure 14.

Each day they said they did their utmost. The work of each day
showed its good effects the following day.

Improved training promotes greater Production as shown in
Figure 13, greater condition is illustrated by lowered cost in heart-
beats in Figure 14 and better Application through regularly de-
clining foot contacts, inning by inning, are graphically illustrated
in the graphs of Figure 13.

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