Unit 105：Ride a bike第105单元：骑脚踏车It provides an excellent aerobic workout.骑脚踏车是一种绝佳的有氧健身运动。Ride indoors on a stationary bike or go outside and enjoy the scenery.在室内踩健身脚踏车或骑脚踏车到室外去欣赏一下风景。Start your muscles and getting your heart in gear.慢慢地开始你每天例行的运动，先花五到十分钟的时间来暖身，让你的心脏进入适合运动的状态。Then speed up for 10 to 20 minutes and finally slow down for another 5 to 10 minutes.接下来加速骑十到二十分钟，最后再慢下来骑五到十分钟。Most stationary bikes help you clock your pace.大部分的室内脚踏车可以计算你踩踏的速度，Set the bike to an easy resistance level and pedal about 40 rpms(revolutions per minute)to start.一开始先把脚踏车速度等级设定在较容易的每分钟四十转，Then increase your pace to 60 rpms and hold it steady for about 20 minutes.然后逐渐增加到每分钟六十转，并以此速度持续踩二十分钟。Finally,slow down to 40 rpms or less for about five minutes.最后，将速度降到每分钟四十转或少于四十转，持续约五分钟。Afterward,walk around the room for a few minutes to let your heart re-adjust to a non-exercise pace.之后，在室内走一走，让你的心跳重新调整回非运动时的频率。And don't jump into the shower right away-that could seriously stress your heart.不要急着去冲澡，那可能会严重地增加你心脏的负荷。