I have many times witnessed an 'Adrenaline rush' on the gym bike.
I set the bike to regulate resistance to keep a constant heart rate.
Off I go and the resistance is pretty high to keep me at 90% of 220 minus age.
After about 40 minutes, the resistance lowers and my pedalling action becomes easier.
Adrenaline has been secreted and as a result, increases my heart rate causing the bikes feedback loop to lower the power requirement to maintain a constant HR.
The same can be experienced on the treadmill where the machine is adjusting gradient to control a constant HR.
After 30 - 40 minutes, the gradient drops and running is easier.
I set the bike to regulate resistance to keep a constant heart rate.
Off I go and the resistance is pretty high to keep me at 90% of 220 minus age.
After about 40 minutes, the resistance lowers and my pedalling action becomes easier.
Adrenaline has been secreted and as a result, increases my heart rate causing the bikes feedback loop to lower the power requirement to maintain a constant HR.
The same can be experienced on the treadmill where the machine is adjusting gradient to control a constant HR.
After 30 - 40 minutes, the gradient drops and running is easier.