Britain's Olympic gold medal-winning former women's hockey captain Alex Danson-Bennett has been forced to retire because of a head injury sustained while laughing at a joke in 2018.

The 34-year-old Danson-Bennett, part of the British team that won hockey gold in Rio de Janeiro in 2016, had hoped to feature at this year's Tokyo Games.

She has been suffering with long-term concussion since hitting her head against a concrete wall while throwing her head back to laugh at her husband's joke while on holiday in Kenya.

Six weeks after the incident she was rushed to hospital with a suspected bleed, being violently sick and having seizures.

The effects have included a "loss of identity," debilitating headaches, light sensitivity and speech problems.

Although Danson-Bennett returned to training in January, she has decided to hang up her stick having earned 306 international caps and scored a joint-record 115 goals.

"The challenge of returning to play following my head injury is too much, and the risk's too high,” she wrote on Instagram.

"After a long 18 months but a fabulous 18 years in the sport, it's the right time for me to retire."

"My head injury has been life-changing, also in terms of my perspective and things that have happened within my family."

Her sister Claire, a triathlete, was paralyzed from the stomach down after colliding with a tractor while riding her bike in August last year.