Swimming-Heart Rate-Calories

ChelzFit

So from my understanding your heart rate is lower by 10-20 beats in the water. When swimming I can get my heart rate up to 135 and on land running it can go as high as 150. When pool running I can only get up close to 130 and I have to work pretty hard. My question is, are the calories my heart rate monitor states accurate during my swim, or am I actually burning more. During a 45 minute session today of swimming/pool running I burned about 300 cals. I feel more exhausted swimming/pool running then I would running on land and seem to burn closer in the 400 range when running on land.