Heald & Tucker. 



Roy. Soc. Proc. B, vol. gj, pi. 8. 



Fig. 12 



NORMAL HEART RECORD BEFORE EXERCISE 



• • i ' ' If 

 it Si . . . ;i 



h ii it 



IMMEDIATELY AFTER EXERCISE 



V I 



- i 





{ 



i 



1 



| 



i 





I 



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Wy I 





60 SECONDS AFTER EXERCISE 



Fig. 13 



