Unit 124：Get physical at least two hours before bedtime
第124单元：睡前两小时不要运动
Regular exercise is great for inducing a good night's sleep,
有规律的运动可促成一夜好眠，
but you may have trouble sleeping if you hit the sack less than two hours after exercising.
但如果你在睡前两个小时内运动的话，可能就会睡不着。
Heart-pumping activity tends to energize you.
因为运动后的快速心跳会使你感到精力充沛。