Which one of the following choices is a good way to overcome lack of motivation as a barrier to physical activity?
a. choose activities that involve minimal risk.
b. invite a friend to exercise with you on a regular basis.
c. schedule activity for times when you’re feeling energetic.
d. identify available time slots for exercising.

Asoccer mom is driving her 75 year old grandmother and her 9 year old daughter home after the game. the grandmother and daughter were both in the back seat and both were wearing their seat belts. a car ran a red light in front of them, causing them to t-bone that car on the passenger side. fortunately there were no serious injuries, but the grandmother did sustain several rib fractures. the mother, daughter and driver of the at-fault car were shaken up but unhurt. what are some possible reasons that the grandmother sustained rib fractures while the other victims did not?