Don’t tell Raju Mantina you can’t find the time to stretch every day. I tried, and he would have none of it.

Fifteen to 60 minutes every night before you go to bed, he says in a tone that leaves no room for argument. “People tell me, ‘I don’t have time to exercise and to stretch,’ ” he tells me in an accent still heavy with the tones of his native India. “I am not one who will listen to this. It’s a total lie.”

There are a lot of massage therapists and trainers out there. I’ve met quite a few in the more than four years that I’ve written this column. Not many approach their work with Mantina’s missionary zeal.

“Movement is an opportunity, not an inconvenience,” he tells me. “That [should be] the mentality of our entire life.”

Stretching and massage are not part of my fitness routine, but I went to see Mantina, 57, last week at the practice he maintains in his Rockville, Md., home. I was just back from a vacation that included four days of strenuous hiking in southern Utah, and my legs, which are always tight, were particularly stiff. A friend at The Post whom Mantina has stretched and massaged for years recommended him.

When I learned that Mantina had worked on athletes at the 2000, 2002 and 2004 Olympics and at four U.S. Olympic track and field trials, I decided to give him a try. My skepticism waned when I saw photos of Mantina with Kenenisa Bikele, the Ethiopian world record holder in the 5,000- and 10,000-meter runs who is widely considered one of the greatest distance runners in history, and Hicham El-Guerrouj, the Moroccan who holds the world records in both the mile and the 1,500-meter races. Mantina’s walls are adorned with photos and posters of other Olympic athletes and with his credentials from those games.

Mantina, once a university-level track and field athlete in Hyderabad, India, volunteers that he was secretly an alcoholic the entire time, for most of his adult life in fact — a bottle-a-day drinker who had previously worked as a gardener and run a liquor store. After he injured his back working in his garden and received massage therapy himself, he decided to change his career. He trained at the Potomac Massage Training Institute and opened a practice. He says he has been sober for 10 months.

I’ve booked a 90-minute session of total body stretching and massage, but by the time Mantina and I finish discussing his philosophy of movement, stretching and massage, there are only 30 minutes left. I suggest Mantina just work on my legs. I describe the wall stretch I do before and after every run, the one you can find depicted in every gym in the land. I am careful to mention that I warm up first.

It doesn’t matter; Mantina is not happy. “You are just putting a load on those muscles,” he tells me, not stretching them. I lean over and try to touch my toes but fall about six inches short. This has always been the case, even when I was young.

Upstairs on his massage table, Mantina gets to work. His fingers quickly find the sore spots in my gastrocnemius muscles, and he begins to stretch them in every direction, explaining that he can’t do anything about my hamstrings until he loosens my calves.

“How are my hamstrings, compared to the average person’s?” I ask at one point. “Terrible,” Mantina responds. At another he says: “You need to lose some weight.”

Okay then.

He begins to loosen my hamstrings, closing his eyes and leaning into them with his shoulder. “C’mon,” he commands when he wants me to push through the pain and stiffness a little more. “C’mon.”

After 30 minutes, I stand, enjoying the loose feeling from my achilles tendon all the way to my hips. I bend over and am four inches closer to touching the floor. Not bad for a half-hour’s work.

Now that he’s getting older, Mantina wants to spend more time teaching, to bring his philosophy of movement, stretching and massage to as many people as he can. He is looking for an assistant to take some of the load off his practice. If people would follow his principles, especially stretching, many would feel so much better, he says.

“You are using your tools all day,” he says of the human body. “You are cleaning them and putting them back, so they are ready for the next day.”