Are these the BEST zones for training?

Fitness Fridays are here! subscribe - it's FREE : https://goo.gl/E9imiU Please like, share, comment & subscribe if you like this video. A new weekly series focusing on different aspects of cycling related fitness & nutrition. The idea is to create a 4 minute video on a specific topic - this weeks it's Endurance (z2) & Vo2 MAX (z5) ------------------------ Music by: Ikson http://soundcloud.com/ikson -------------------------- Media Locations: https://www.strava.com/athletes/311841 - my Strava https://twitter.com/SRussellPhotos - Twitter https://www.instagram.com/srussellphotos/ - Instagram https://mixer.com/srussell73 - live streams https://www.twitch.tv/srussell73 - TwitchTV : gaming streams