MADRID (AFP) - At a rehabilitation centre inside a Madrid hospital, Covid-19 patients drag an oxygen tank with them everywhere, even when exercising on a treadmill.

Although the vaccines have raised hopes that the pandemic will soon end, many who are battling to get over a serious bout of coronavirus continue to struggle with breathlessness, fatigue and mobility problems.

"I can't walk on my own," admits Ms Carolina Gallardo, 51, who is having to learn how to walk again at a rehabilitation centre at Isabel Zendal hospital.

"I can't use my hands - look at my hair, I can't even put it up on my own."

Pulling herself up from her chair, she clings on tightly to the parallel bars, slowly moving her foot in what is obviously a huge effort.

With an arm around her waist, a physiotherapist gently urges her on, encouraging her to put her weight first on one foot then on the other.

Built in just three months at a cost of over €150 million (S$240 million), the Isabel Zendal Hospital opened its doors in December to treat Covid-19 patients although its rehabilitation centre was only inaugurated this month.

Inside the centre is a treadmill, exercise balls and a ramp as well as wooden blocks and a large mirror so patients can check their posture.

Here, experts help recovering Covid-19 patients who struggle with continued respiratory problems or have lost their "motor capacity, to the point that holding a spoon or opening a bottle" is impossible, explains Dr Jose Lopez Araujo.

Patients walk around with electrodes attached to their bodies, or with a pulse oximeter on their finger, a device that monitors the pulse rate and oxygen levels in the blood.

On the wall is a poster with a quote from Rocky, the 1976 hit film about an underdog boxer: "Going one more round when you don't think you can, that's what makes all the difference in your life".

A survival miracle

Ms Gallardo has come an awful long way since being in the intensive care unit, which she barely remembers.

"I'm a miraculous survivor. I shouldn't have made it," she says breathily, a transparent tube connecting her nose to an oxygen tank.

She has only recently recovered her ability to talk.

"I couldn't close my mouth. A physiotherapist has been working with me on stretches so that I can close my mouth.

"I could hardly speak, I couldn't even hear my own voice, but then I started hearing it and now I'm talking," she explains softly "It's a devastating disease."

Mr Jesus Nogales, 68, spent about a month in intensive care.

"I was unconscious, sedated, I had no idea what was going on. For me, it was like the world didn't exist," he told AFP.

When he finally came round, he was devastated to learn that his wife of 51 years had died of Covid-19.

Racked by grief, his body just shut down.

Limbs 'like jelly'

"When I left the intensive care, it was like my whole body had turned to jelly. I had absolutely no strength. I had to relearn how to walk, to eat, and to move," he says.

"I remember them giving me a solid meal of rice and when I took the first mouthful, I thought it wasn't cooked because I had no strength in my jaw to chew," he says.

He has since regained the ability to eat properly, happily listing the foods he can once again enjoy.

Like many Covid-19 patients, Mr Nogales lost his sense of smell when he first caught the virus and says he could have easily picked up "a glass of bleach" without realising it wasn't water.

He is now working with physiotherapists at the centre to get his lung capacity back to normal.

"I don't want to end up in a wheelchair," he says.

Spain has been hit hard by the pandemic, recording more than 77,000 deaths from over 3.4 million cases.