Hello,
As
ultrasound sound scanning is good for finding any blood clot in the calf region.
Since it's negative I think you may have a muscle imbalance which is not allowing the biomechanics of the muscles of the leg to have a proper contraction.
I will advise you to start the balance board training is one, then try doing reverse jogging, reverse walking, and picking the marbles with the help of the toes.
This will help improve the muscle imbalance in the lower legs and improve you sports activities too.
Also please have a check to your footwear as it may have some differences which aren't matching the requirements of the foot.
In my clinical practice of over 12 years, this complains are often and we treat accordingly after having a clinical examination but balance board training has found to be more effective.
Hope I have answered your query. Let me know if I can assist you further.
Take care
Regards,
Jay Indravadan Patel, Physical Therapist or Physiotherapist