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These super-fit women can lift weights without breaking a sweat. But the one place that isn’t their strong point is the bedroom.

New research shows too much exercise can kill your sex drive. The University of North Carolina studied people’s exercise habits and libido levels. It found those who train for a long time at high intensity suffer an almost instant loss of sex drive.

Exhaustion from training leaves some too tired to perform while pushing yourself with extreme exercise can lead to an under-functioning pituitary gland, meaning low levels of testosterone and estrogen.

Women also need a certain level of body fat for the reproductive system to work effectively.

Too much exercise and too little body fat can cause it to shut down, nipping passion in the bud.

Here, fitness fans reveal how working out in the gym and enjoying hard training has affected their love life.

"My libido’s vanished"

Nikki Harvey worries that her “zero sex drive” will push away her 26-year-old partner Jordan Burgess, a personal trainer.

Nikki, from Wolverhampton, a city 125 miles north-west of London, was an overweight smoker who did not exercise but has transformed her body in three years. She says:

“In the autumn of 2014, I was a size 16, drinking, smoking, living off junk food and generally pretty miserable.”

“One night I met Jordan and we quickly became an item.”

“He’s a rugby player and he caught me crying to myself in my bedroom when I couldn’t fit into my size 14 clothes.”

“He told me anyone can turn their life around and inspired me to get healthy and take up fitness and bodybuilding.”

“I signed up for a 14-week intensive program, pushing me harder than I ever dreamed possible. I loved every second.”

“Every gram of excess weight was stripped from my body – better than any faddy diet.”

“I now train every morning at 5:30 a.m. for two hours, then do an hour’s cardio every evening.”

“It really impacts on my relationship. I haven’t been on a date night with Jordan since January and my libido has vanished.”

“Right now I have zero sex drive so Jordan and I haven’t made love for two months. Jordan hates it but he knows it’s not because I don’t fancy him. I love my training so much that two months ago I quit my job to do it full time.”

“In April I came second in the UK Bodybuilding and Fitness Federation National Finals and qualified for three inter-national champion-ships.”

“My libido might be gone but I look better and am now so much healthier.”

“I just hope that Jordan will stick by me without sex.”

"I don’t need a relationship"

Fitness addict Gabriella Prior, 22, from Bournemouth, a city 100 miles south-west of London, would rather be in good shape than have a sex life. Gabriella has not had sex for more than 18 months. She says:

“At the start of 2016, I did almost no exercise. I went out drinking, enjoyed lazy weekends, had boyfriends and a healthy sex life. I wasn’t depressed but I felt like I didn’t have any hobbies.”

“One morning, on a whim, I decided to join the nearby House of Pain boxing gym. I was nervous but when I left I was so full of energy I couldn’t wait to do it again.”

“Exercising is now like a drug to me. Within weeks I was training twice a day for two hours each session, five or six days a week. I still do that now.”

“It’s 100 percent effort training with weights, sparring and cardio. Boxing isn’t a sport you do by halves. I can hardly tie my shoe laces after I have finished a session, let alone think about sex. I used to have boyfriends but they ran their course.”

“Now I don’t have time to meet men. I have realised I don’t need a relationship or sex to be happy. I value independence and fitness more than I thought possible. My sex life now is a dim and distant memory.”

“I hope that if I ever want to, I can reduce the intensity of my training and then get my libido back. But I’m not bothered now.”

“I’ve had a couple of short-lived relation-ships since I started training but quickly I’ve been dumped because they thought I was boring, as I did not want to have sex all the time.”

“I have been crowned Miss Fitness Inspiration UK, which means more to me than any amount of sex.”

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