Caitlyn Jenner feels ''wonderful'' not having any more secrets.

The 'I Am Cait' star - who was known as Bruce Jenner before she underwent a gender transition in 2015 - feels blessed to be able to share her true identity with the world and has spoken of the relief of not having anything else to hide.

She said: ''I don't have a secret left in my life. It's a wonderful feeling. The book is about a lifelong struggle. Everybody has their stuff. Everybody has things that they have to deal with in life, and what I've dealt with my entire life is my identity with myself as a person. To be able to share that journey with people ... feels great.''

And the 67-year-old television personality believes she threw herself into sport because of her ''issues with her gender''.

Speaking on Live! With Kelly, she added: ''You're not talking about sexuality - you're talking about who you are and who's in your soul. It goes through your head 24 hours a day, 365 days a year ... I grew up in the 50s and the 60s - there wasn't even a word for it. I didn't know what it was. I didn't know why. Sneaking into my mom's closet or my sister's closet ... walking around when I was 9 or 10 years old ... [with] a scarf over my head so it didn't look like I was a girl ...

''I look back on it now and a lot of the reasons why I was so obsessed with winning the games was because of my issues with gender. I was also a dyslexic kid so I suffered from low self-esteem, and all of those things would come into play. I was more determined. I was going to outwork the next person, I was going to out-train the next person, and I was going to be smarter. I didn't know how far I would go.''