Are you warming up enough for the movements you will be performing?
You are seeing an issue with your hamstrings, but it doesn’t sound like this is where the issue starts.
Are you in an organized start position, breathing properly, maintaining good positioning throughout your movement patterns/technique?
We’ve all seen the demo where it looks like the person has tight hamstrings and after getting organized and exhaling the breath the hamstring range improves alot.
Have you looked up/down stream of your hams?
Pro Episode # 21 – Pro-User Request Friday: Not Seeing The Change? You Need a Systems Approach.