Great Britain and England captain Alex Danson has revealed how laughing at her fiance's joke led to the "most challenging" period of her life.
The 34-year-old is, somewhat bizarrely, one of three 2016 Olympic gold medallists who have been sidelined by concussion in the last 18 months.
However, while Nicola White and Shona McCallin sustained their injuries on the pitch, Danson's was purely accidental in a social situation while on holiday in Kenya with her boyfriend, coincidentally also called Alex.
"He told a joke and I flung my head forward in laughter and then flung it back pretty quickly and I hit my head flush on a concrete wall," Danson told BBC Sport.
"It was hard but equally it wasn't a car crash. I didn't fall from a great height. There was no seemingly huge trauma at the time but I knew something wasn't right.
"We were on holiday for another couple of days and getting home was a nightmare. I was very unwell. I had my hands on my head at the airport, I was crying.
"By the time I got home, I wasn't well. I had terrible headaches, light sensitivity, noise. I came back and I was in bed in a dark room for a month."
Six weeks after returning home she persuaded the team doctor she was fit enough for a team-bonding away day pottery painting.
"I went for an hour and all I remember was talking to my team-mate next to me and I lost the ability to speak. I just couldn't say any words," added Danson, who is scheduled to get married in September.
"Obviously I was frightened but I didn't want to cause a scene so I went back to painting my egg cup. I went home as soon as that session was done.
"I was very sick. I don't remember much. I went to hospital, I was very unwell.
"The next few months were really challenging. I was in bed 24 hours a day. I could hardly walk to the bathroom.
"I couldn't bear light, sound, touch, anything. It was almost like my sensory dials had been whacked up. Even holding a conversation, I'd have to talk very slowly.
"I've improved hugely and headaches are my predominant problem. Light is still quite bright and noise can make me feel unwell."