Pedro Pascal's personal trainer turns 50 this year and feels healthier than ever. Here's how he eats and trains.

• Jason Walsh is a personal trainer who has worked with Matt Damon, Camila Mendes, and Pedro Pascal.

• Walsh approaches his health with his physique but also his longevity in mind.

• He prioritizes strength training and has eaten a mostly plant-based diet for 10 years.

The celebrity personal trainer Jason Walsh sees his health as an investment. Approaching his 50th birthday, he's feeling fitter than ever.

In Walsh's early 20s, his dad died of a heart attack at the age of 40, and his uncle John became his father figure, he told Business Insider.

"He was an incredible man," Walsh said. "He spent a lot of time in nature, had a huge stature, and was always really fit. I really looked up to him."

John instilled in Walsh the idea that you only have one mind and body, so you should look after it.

After seeing that lifting weights improved his baseball skills growing up, he was motivated to keep training.

"Also the girls started paying attention. That was definitely a positive outcome," Walsh said.

He went on to qualify as a strength and conditioning coach at the University of North Carolina and started working with athletes before becoming a personal trainer in Los Angeles. Over his decadeslong career, Walsh has trained actors including Jake Gyllenhaal, Camila Mendes, Matt Damon, and Pedro Pascal.

Walsh shared how he trains and eats to balance staying in shape with being healthy for as long as possible.

Strength training and conditioning year-round

Like many people, Walsh used to be more driven by looks than health but now balances aesthetics with longevity and functionality — in the hope his body will move well and support him for the rest of his life.

However, he still tweaks his routine slightly throughout the year to maintain his physique.

In the autumn and winter, Walsh focuses on lifting heavy weights to build muscle, while in the spring and summer, he does more conditioning including cardio and circuits to raise his heart rate and help him lose some body fat.

"Does it suck when I start doing the conditioning? Absolutely. I hate it," Walsh said. "I like to train heavy."

Walsh is a big fan of testing and tracking his progress. He regularly measures his body composition — using an InBody scanner or skin fold calipers when he's traveling — and has his blood work done to check his vitals.

Nailing the basics: Sleep, nutrition, and hydration

To help his body recover from workouts, Walsh focuses on the basics of: sleeping enough, eating a high-protein diet including a balance of carbs and fats, and drinking plenty of water.

Walsh used to eat a lot of red meat, dairy, and whey protein. But after tests revealed he had high cholesterol and early signs of arterial sclerosis at age 40, he decided to experiment with eating more fruits and vegetables. He has been predominantly plant-based, occasionally eating fish, for a decade. As well as his father, Walsh's grandfather and brother died of heart attacks.

Eating fewer saturated and trans fats, commonly found in foods such as red meat and full-fat dairy products, and eating more fiber and healthier fats, can help with reducing high cholesterol levels.

The next time Walsh had his blood work done, he saw vast improvements.

"I was intrigued that something so simple, my habits, could potentially save my life," he said.

While he misses cheese and dairy, Walsh said he can still consume enough protein through vegan sources, including his own plant-based protein line, Rise311.

Staying disciplined

Walsh feels lucky that John taught him about discipline when he was young. He acknowledges that prioritizing fitness is easier for him than those with responsibilities like a partner or kids, but said it can be learned at any age, providing you're willing to put in the work.

"Achieving this lifestyle is something that must be learned — it requires discipline and sacrifice. If you're willing to commit to both, it can profoundly impact every aspect of your life. For me, there is no alternative."

He added: "Getting discipline in your blood is one of the greatest things that you can ever achieve."

That same discipline saw him turn down parties in college so he could work on his career and fitness goals and it's the same discipline he sees in the CEO clients who go to his gym at 5 a.m., he said.

Read the original article on Business Insider