Like a couple people have said, this is nothing new--it's an affirmation at most. But what also is missing is that it is completely reliant on the individual. Warmups are RELATIVE to YOU, the athlete.
I played 3 varsity sports--soccer, swimming, and track--throughout my 4 years of high school but made sure that I did a dynamic stretch of MY OWN before getting into any stretching/exercise with the rest of my team. I stayed healthy throughout high school. When I got to college, I decided to play ultimate frisbee and made the A team. I became lazy and started stretching with the team--the coach had us do a relatively rigorous dynamic stretch. I wasn't a fan but went along with it (again, I was lazy). About 5 weeks in, I pulled my hamstring badly and it took me about 6-8 weeks to fully recover. I don't want to jump to the conclusion that not doing an individual dynamic stretch was THE reason for my injury, but it definitely was a large contributing factor. From the time I came back until now, I make sure to do my own dynamic stretch before getting into any exercise, light or intense--it works.
WHY?
The whole point of stretching is really to get your muscles moving and to be comfortable. Only I can decide when I feel I am ready to go...and only you can decide when you are. So do what you feel is best for you first, then immerse yourself in activities that your peers or team is doing. And I promise, this will not be held against you as doing something that the team is not. Hell, I was the captain of my swimming and soccer teams for my junior and senior years. If you're helping yourself, you're ultimately helping the team--especially in this context.
Warmup and stretching are orthogonal to each other. Warmup is important, stretches pre-exercise are not and may be harmful in terms of injury risk for that workout. Doing dynamic stretches overall is good improving your flexibility, though. Overall you might very well have done yourself more good than harm, but you'd likely do yourself even more good by warming up a different way and doing your dynamic stretches at a different time.
"Getting your muscles moving" does not require a stretch, you can keep your movements well away from pushing your range of motion.
I played 3 varsity sports--soccer, swimming, and track--throughout my 4 years of high school but made sure that I did a dynamic stretch of MY OWN before getting into any stretching/exercise with the rest of my team. I stayed healthy throughout high school. When I got to college, I decided to play ultimate frisbee and made the A team. I became lazy and started stretching with the team--the coach had us do a relatively rigorous dynamic stretch. I wasn't a fan but went along with it (again, I was lazy). About 5 weeks in, I pulled my hamstring badly and it took me about 6-8 weeks to fully recover. I don't want to jump to the conclusion that not doing an individual dynamic stretch was THE reason for my injury, but it definitely was a large contributing factor. From the time I came back until now, I make sure to do my own dynamic stretch before getting into any exercise, light or intense--it works.
WHY?
The whole point of stretching is really to get your muscles moving and to be comfortable. Only I can decide when I feel I am ready to go...and only you can decide when you are. So do what you feel is best for you first, then immerse yourself in activities that your peers or team is doing. And I promise, this will not be held against you as doing something that the team is not. Hell, I was the captain of my swimming and soccer teams for my junior and senior years. If you're helping yourself, you're ultimately helping the team--especially in this context.