单项选择题

As a fitness coach in Grand Rapids, Mich. , Doreen Bolhuis has a passion for developing exercises for children. The younger, it seems, the better. "With the babies in our family," she said, "I start working them out in the hospital. " Ms. Bolhuis turned her exercises into a company, Gymtrix, that offers a library of videos starting with training for babies as young as 6 months. There is no lying in the crib playing with toes.
Infant athletes, accompanied by doting parents on the videos, do a lot of jumping, kicking and, in one exercise, something that looks like baseball batting practice.^①
The growing competition in marketing baby sports DVDs includes companies with names like athletic Baby and Baby Goes Pro. Even experts in youth sports seem startled that the age of entry has dipped so low. "That’s really amazing. What’s next" said Dr. Lyle Micheli, an orthopedic surgeon.
Dr. Micheli said he did not see any great advantages in exposing babies to sports. "I don’t know of any evidence that training at this infancy stage accelerates coordination," he said. One of his concerns, he said, is "the potential for even younger ages of overuse injury. "
The Little Gym, based in Seottsdale, Ariz. , begins classes for children at 4 months old. Bob Bingham, the company’s chief executive, said that about 20,000 youngsters under 2—about a quarter of the total enrollment— were signed up for classes at locations in the United States, Canada and Puerto Rico. That is a sizable increase from last year, he said. The company, which has gyms in 20 countries, plans to open 100 locations over the next five years. My Gym, based in Sherman Oaks, Calif. , said 55 percent of those who attend classes at its 200 locations—157 in the United States—were 2 or younger.
The entrepreneurs behind these businesses—gym teachers, accountants and former professional athletes among them—make no claims about turning today’s babies into tomorrow’s Super Bowl star.^② In the past, marketing claims for products geared toward babies have caused trouble for companies. Disney, which owned the popular Baby Einstein brand, dropped the term educational" after a children’s-rights group objected to contentions that babies who watched "Baby Einstein" were learning, ^③ Disney also offered refunds.
That’s not enough to sell Dr. Micheli on the idea of sports classes for tykes. Betore rushing off to a day of treating injured athletes, he said, "We won’t be putting their brochures in our clinic. \
Which is the best title of the passage