Howey, the only British woman to have won two Olympic judo medals – silver in Sydney and bronze in Barcelona – has coached Howell since the Stafford-born judoka was just 13 years old, seeing her overcome multiple injuries throughout her career.
Competition is fierce in British women's judo in the lead up to Tokyo with both Sally Conway and Howell competing for the same weight category.
But for Andover-born Howey, the tenacity shown by the latter to win gold in Budapest and Zagreb and bronze in Brazil following back-to-back knee and neck operations proves she has the mental strength to succeed.
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"They just keep jumping each other in terms of the qualification so Gemma just has to keep plugging away getting the results that she's been getting lately and stay injury-free ahead of next year," said Howey.
"She has wanted to win gold at Tokyo ever since the age of 13. She's had some hard times through injuries, so she's always had that mantra of Olympic gold and that's what she believes in and that's what she wants.
"She's such a giving girl, too. She works so hard, one of the hardest workers we have. Who knows what will happen on the day."
Howey was speaking at the Olympic Park in Stratford, where she joined 25 past and present British athletes to mark the 25-year anniversary of the National Lottery.
Since the National Lottery's first draw took place on 19 November 1994, more than £40 billion has been raised for good causes in the areas of arts, sport, heritage, culture, film, charity and community, with more than 4,500 elite athletes receiving grants enabling them to access the best coaching, facilities and support staff in the world.
Before funding began for elite sport, Great Britain were ranked 36th in the medal table at the 1996 Atlanta Summer Olympics, but at Rio 2016 – after almost two decades of funding – Team GB finished second.
Two-time Olympic medallist Howey came through the ranks in this era to become the first British judoka to have competed at four Olympic Games – a feat that she knows would have never been possible without National Lottery's support.
"The National Lottery for me has been a godsend," said Howey.
"As an athlete, I was funded from 1997 all the way through to 2004 when I finished and now, I'm employed as head coach for British Judo which is funded by UK sport national lottery.
"I'm old enough to remember Atlanta, where it was a bit more dismal and then obviously the Lottery came in in '97. Then to watch GB grow has been unbelievable.
"I know people go out and buy a lottery ticket, but every little helps and that's what funds the greatness in our sport at the moment."
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