Lambert spoke with E! News at the Wednesday event, which saw the country star take home four awards, breaking a record. Wearing short skater dresses, she and Trainor performed a duet of the latter pop star's hit single and positive body image anthem "All About That Bass."
"She's got like, some moves and she's like, 20 and I'm 30, so there's that gap," Lambert said. "I'm like, ‘Woah, I need some coffee.' When she walks in the room, she has so much energy! I was like, ‘Woah, I gotta perk up!'"
Is it me or does Miranda lambert seem bored and over it tonight?? emeline osburn (@EmelineOsburn) November 6, 2014
Also, Lambert had woken up super-early for the evening performance.
"I've had a long day. I was up at 4:45 this morning, so it's kind of been a whirlwind," she said. "I think I'll be celebratory for a while and after I have some pizza, I'll probably crash."
Trainor, whose single was recently bumped on the Billboard Hot 100 Singles Chart by Taylor Swift 's "Shake It Off" after topping it for 16 weeks, also got playful off-stage, stealing Lambert's country music star husband Blake Shelton's cellphone for a quick selfie.
"Sooo.... I left my phone in my seat for a minute last night..." he tweeted.
Lambert won four CMA Awards this year, including a preliminary win with Keith Urban for "We Were Us" for Musical Event of the Year, announced on Good Morning America, and a fifth consecutive win for Female Vocalist of the Year. With 11 awards in total, she is now the female artist with the most CMA Award wins. Shelton, who won Male Vocalist of the Year, tweeted every time his wife won an award on stage.
She's up to 3!!!? Blake Shelton (@blakeshelton) November 6, 2014
That's 4!!!!? Blake Shelton (@blakeshelton) November 6, 2014
Check out more interviews with artists and bands at the 2014 CMA Awards, including Luke Byran, who was named CMA Entertainer of the Year, Lady Antebellum, The Band Perry, Florida Georgia Line and Urban and wife Nicole Kidman.