newbie-pulse lower at canter?

[drhopkins@greenapple.com]

Hi all,

New to training, but want to do everything right.  Have pulse rate monitor that 
I started using during training rides last fall.  Live in OH so took shoes off 
for winter early Dec. and gave him almost one and half month off.  Was very 
sensitive on his feet.  Trying easy boots and riding him some.  Pulse rate was  
higher with boots than without them.  Added a Shocktamer pad and tape then only 
put on front feet for a short road ride.  Pulse was still high, also seemed 
higher at a walk than trot.  Let him pick up a canter, out of curiosity.  He 
went fine and his pulse rate dropped to lower than a trot.  Couldn't believe it 
so walked for 10 mins, pulse went up.  Went to a canter, pulse went down some.  
Still didn't think it was right.  This time cantered him up a hill.  Pulse 
still lower.  If he's uncomfortable with the shoes or being barefoot, why would 
he be more comfortable at a canter than a walk or trot?  What am I missing?  He 
is an ex-racehorse(9 years ago) and he does love to run. It's got me puzzeled.  
Any suggestions, comments?

Thanks,
Anna