When a chakra is realy open, siddhis - spiritual power hidden in - begin to work. Untill yogi do not obtain siddhis, chakra is not open.
For example see chakra Anahata:
Anahat Chakra or heart chakra: If one contemplates (contemplation = a long term meditation) on the flame called vanlinga that resides in the heart chakra (anahat chakra), he attains knowledge beyond measure. He attains clairvoyance and can see the past, present and future. He can walk in air (khechari siddhi) and travel anywhere (Bhuchari siddhi). Through his clairvoyance he can perceive the yogins..............................................
There is a many nonsense about chakras in Western countries. I recommend to read the translations of the original texts of the East.
Good books about are transalntions by John Woodroffe - Arthur Avalon - for example like Sat chakra nirupana, Paduka panchaka, The serpent power and so on. Or a good books are Shiva samhita a Gheranda samita.