What is the best time of day to have your client measure their resting heart rate?

It is recommended to measure your resting heart rate in the morning after a day of rest, after wake up.

Explanation:

  Heart rate means the number of heartbeats in one minute. The two most common ways to describe heart rate are in beats per minute and as a percentage of the individual maximum heart rate.  Heart rate at rest represents the lowest heart rate when you are awake and at rest.  

  It is a useful tool if you want to know more about your sports performance. By training by measuring your heart rate, you can monitor and control the intensity of your workouts.

   It is recommended to measure your resting heart rate in the morning after a day of rest. The measurement should be performed in the morning immediately after awake.

no because dogs are cats the product you bought is meant for cats xd