Hi bella lucia,
a pulse of 40 is nothing to be overly concerned about, especially as you are physically fit anyway. A fit person or athlete will normally have a much lower pulse or heart-rate as the heart muscle is much more efficient......................
"The pulse varies greatly during a fast. It may run up to 120 or even higher, or it may drop as low as 40, per minute. Indeed, Mr. Macfadden records a case in his practice in which the pulse went down as low as 20 and was so feeble it could scarcely be felt. It is the usual thing to have the pulse rate increase at the beginning of the fast and then, after a day or two, to drop. In chronic cases that are confined to bed during the fast, the pulse usually, after its temporary rise, drops to 48, or 40, where it may remain for a day or two days and then mounts up again to 60. After a few days it will settle at 60 and remain there until eating and activity are resumed. It is, of course, understood that the pulse is subject to all the variations, while fasting, as at other times of life, and that where there is "disease" of the heart, or nervous troubles, it will often vary greatly from the above standard. Where stimulants are employed during a fast, these occasion more heart activity than if taken when one is eating."
Your previous blood pressure is probably a little on the low side, but equates to being very healthy. The top number you have given of 110 (systolic) is in proportion to your diastolic of 70; normal BP is an ideal of 120 over 80, and is used as a guide only. High BP is anything above 140 systolic, so please do not cause yourself any unnecessary anxiety.
BP wrist monitors can also give you your pulse, as does my own, which is a Braun and found to be very reliable. They are not expensive.
Only take your BP though at the same time of day every day, such as when arising in the morning. It is important to take your BP after rest, and not after activity to give an accurate assessment.