Even though Tai Chi is slow and gentle doesn't leave you out of breath, but it does address the important components of fitness.
Muscle strength, Flexibility, Aerobic Conditioning
Flexibility, aerobic conditioning and to a certain extent aerobic conditioning can by doing Tai Chi.
“Muscle strength. Tai Chi can improve both lower-body strength and upper-body strength. When practiced regularly, tai chi can be comparable to resistance training and brisk walking”, said the Harvard Medical review.