Though it's tempting to sleep in, it's preferable to exercise first thing in the
morning. A recent study measured the sleep cycles of people who exercised at 7
a.m., 1 p.m., and 7 p.m. It found that those who exercised at 7 a.m. experienced
deeper sleep than everyone else. These people also had a 10 percent reduction in
blood pressure during the day. Another study found that those who exercised in the
evening had better workout performance. Evening exercisers are also less prone to
injury because their muscles are already warmed up.
What weakens this argument?
A. the evidence that exercising in the evening results in better workout performance
B. the evidence that those exercising at 7 a.m. experience deeper sleep
C. the evidence that exercising in the morning can reduce blood pressure