Feeling low isn't something we openly admit - at least not to everyone. It's sometimes perceived as a weakness, something to hide.
Be that as it may, we all feel down sometimes; so ensuring we create habits that will improve our mood is essential.
Gemma McCaw knows a thing or two about feeling down; she has previously written about 'feeling broken' after she missed out on a medal at the London Olympics and about the tough decision of whether to continue playing hockey.
Since then the Olympian has moved on from hockey and turned to helping others - she's written about embracing change, eating well and staying positive.
We've compiled a list of Gemma's most important words of wisdom in the above video.