I would say Gymnastics is impossible and I have a friend who would say the exact opposite. So it's up to you.
gimnasia
To say 'I have a microwave' in Spanish, you would say 'Tengo una microonda.'
gymnastics = Gymnastik
To say 'I have a notebook' in Spanish, you would say 'Tengo un cuaderno.'
To say 'furniture shop' in Spanish, you would say 'muebleria.'
To say 'knives' in Spanish, you would say 'cuchillos.'
To say 'evaporation' in Spanish, you would say 'evaporación.'
To say 'decompostion' in Spanish, you would say 'descomposición.'
To say 'condensation' in Spanish, you would say 'condensación.'
To say 'rich' in Spanish, you would say 'rico.'
I would say it does because both sports focus on flexibility and strength and by doing gymnastics it will make karate easier.