An article published in December 2023 in the Journal of Applied Physiology talks about a man in his 90s who is physiologically as fit as a 40 year old due largely to a simple routine of exercise and good nutrition.

Researchers found that measures of his heart health, muscle mass and overall fitness were more comparable to that of a healthy 30- or 40-year-old. His habits, included regular strength training, low-intensity cardio and good nutrition, Evidence suggests these are all established ways to extend your lifespan and stay fit.

Here are the factors found in the case study that may have helped him be fit and healthy in his 90s:

Low intensity cardio

For the case study, the researchers analysed Morgan's training, which included about 30km each week on the rowing machine. They found that about 70% of his workouts were at a light intensity level. That's almost perfectly aligned with what doctors and exercise scientists recommend for cardio training to improve longevity, endurance and all-around performance.

Include bursts of max effort

The rest of Morgan's aerobic training comprises around 20% moderate intensity and about 10% high intensity, such as an all-out sprint. The latter is important because researchers found the man had a remarkable ability to use oxygen effectively.
Evidence suggests shorter, intense periods of exercise at a pace you can't sustain for long, are ideal for building this kind of fitness.

Lift weights

The researchers also found Morgan supplemented his rowing with two days a week of strength training with weights.
Extensive evidence suggests he has the right idea. Studies have found weight training can help avoid chronic disease. Research suggests 30 to 60 minutes a week of strength training is more than enough to make a difference.

Eat protein

The case-study researchers said that in addition to exercising regularly, the gentleman had a high-protein diet. Getting enough protein may have helped him maintain a high amount of muscle mass along with a low body fat of 15%, on par with a fit, younger man.

It's never too late to start exercising

Besides his exceptional fitness, one of the most distinct parts of Morgan's case study was that he began his exercise routine relatively late in life, starting to row as a hobby at 73. Before his 70s, the researchers wrote, he didn't consistently exercise.
Evidence shows that even people who start training in their 80's and 90's can benefit from exercise and gain muscle mass and strength, which can have benefits for health and quality of life.

Consistency

One reason Morgan may have been so successful in seeing health and fitness improvements is that he was extremely consistent with his routine, the researchers said.

Physical changes related to diet and exercise take time, whether that's building muscle, burning fat, or improving your health. That's why experts generally don't recommend crash diets or fad workouts. No matter how optimal a diet or workout routine is, you won't benefit if you stop doing it, so the best longevity plan is something you can stick to for the long term. (Source: businessinsidercom)