List and explain the most common dangerous conditions that increase the chance of getting injured in sports.

A concussion is a traumatic brain injury that alters the way your brain functions. [ Effects are usually temporary, but can include problems with headache, concentration, memory, judgment, balance and coordination. Signs and symptoms of a concussion may include: Headache or a feeling of pressure in the head Temporary loss of consciousness Confusion or feeling as if in a fog Amnesia surrounding

Nail fungus, which can cause the nails to crack, peel and change color and texture.