2wks ago 45min cycle AVG heart rate 157.Now cant get more than 140 doing same thing.Why is this?

Answer:
Ahh good question.
Well, due to the continuous exertion you have been putting your body/heart through during your excersize, you heart has become "fit" to handle the high blood pressure of the excersize and has adjusted itself to allow for a better heart rate to control your Oxygen and CO2 getting it out of your system easier. This means you are on the road to fitness. If you keep doing this you can avoid tacycardia (irradic rythms of the heart) and high blood pressure because your heart will have adjusted and will be healthier. This will mean that you have less of a chance for a heart attack later on in life as long as you continue excersizing as well as a healthy diet.
I challenge you, try again these next 2 weeks cycling 45 minutes a day.. on the 14th day, take your heart rate, I bet you it will be lower!Good luck and Good health to you!

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Your body has learned to get into better shape and can now do more aerobically to lower your heart rate and make your body be more efficient. If you want to raise your heart rate, you are going to have to ride longer and/or faster to challenge your body more.

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Congratulations, youve improved your aerobic efficiency.
Don't sweat it. - It's a good thing.

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Your muscles have gotten used to the activity and your body doesn't have to work as hard anymore. Cross train!

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Because you are in better shape now...it will take more effort to get your heart rate up.

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time for new machine?!

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