Opponents should never make the mistake of judging her on her demeanour away from the mat.
When she is in fight mode, she is focused, aggressive and explosive. Outside of competition, she gives the impression she is happy-go-lucky and takes everything in her stride.
It is a good attribute to have considering she could be burdened with being one of Scotland's gold medal favourites at this summer's Commonwealth Games. And this before her place has even been confirmed.
Not that there will be much doubt about it. The seven highest-ranking Scottish women will be chosen for Glasgow 2014 and, in the heavyweight category, Adlington is ranked 17th in the world in the latest lists. Significantly, she is also the top-ranked Commonwealth judoka with the next highest, England's Karina Bryant, at 44th.
Adlington will seek to clamber even higher up the rankings before the month is through. Today, she is in action at the Paris Grand Slam, next week it is off to Rome for the European Open and, the week after, she chances her arms at the Dusseldorf Grand Prix.
She has trained and fought all over the world but the International Judo Federation's propensity for changing the rules means she will be on unfamiliar territory today. Since the start of the year, women's matches have been reduced from five minutes to four which will alter the tactics adopted. It adds another degree of uncertainty.
"It'll be the same for the Commonwealth Games and it will change things. For me, if I'm fighting someone much bigger, then I'll not try to throw them until they are tired. But the new rules mean there is less time," she says. "Until I've fought, I don't know how it will be, but I can imagine four minutes will just fly by. It's everything but it's nothing."
Adlington was fifth when she last competed in Paris two years ago and looked on course for London 2012 but she ended up watching the Olympics from a hospital bed in Glasgow.
A troublesome shoulder injury meant she had to have an operation during the Olympics - she was to be away from the mat for a year - and could not be in attendance to watch Edinburgh clubmate and close friend Sally Conway compete. It was a bleak time.
"It wasn't the best of circumstances," she understates. "I'd trained however long to be at London and I wasn't there. So that was an emotional time for me. It was probably the worst time of my life but they say what doesn't kill you makes you stronger. I think it certainly makes you more determined to get to wherever you want to go.
"It was just wear and tear more than anything. I knew ages beforehand that I would need an operation as it was really sore. I didn't want to go to London not fully fit and then think, what if? So it was for the best."
She had the support of both her family and her second family at her training base in Ratho. Born and brought up in Shrewsbury, Adlington moved to Scotland aged 17 to further her judo career. She appreciates the time invested in her by her coaches and, when Glasgow was awarded the Commonwealth Games, there was no question which country she would be competing for.
"My family in England are happy as long as I'm happy and the support I've received up here through Judo Scotland and Edinburgh Judo Club has been amazing. Scotland is where I've lived most of my adult life and it would be like fighting for the enemy if I chose England now. Obviously, my coaches have had a lot to do with my judo over the past 10 years and I couldn't go against them.
"As soon as I moved up here, Euan [Burton], Matt [Purssey] and Sarah [Clark] looked after me and made sure I was all right. There was always guidance here to help me make the right decisions which maybe teenagers who leave home to go to university don't have.
"For the first five or six years, it definitely felt like a tight, family atmosphere. It made training easy, or rather easier, as training isn't easy."
Being a heavyweight, there are few female sparring partners for Adlington and certainly not at the level she needs to stay sharp.
"I've pretty much been training with men for the last 10 years," she says. "It was good to go to the European training camp in Austria last month as I managed to get some training with heavyweight women and I came back more confident. It felt really good chucking them about, and it's not the same feeling you get when you're training with men. But if I didn't train with the men, I wouldn't have anyone to train with here. Many other countries are in the same boat. It's only really the French, the Germans and the Japanese who have quite a few heavyweight women."
Adlington is now throwing everything into her Games preparation and knows there could be expectations on her shoulders this summer.
"If you are favourite to go into any tournament, there is pressure and you have to find a way to deal with it," she says. "It can be a bit easier when no-one expects anything - a bit like lower league teams playing Manchester United - but, if that's the case, I just have to handle it."