Calorify's Impact on Endurance Athletes: A Journey with Founder & CEO Hari Mix

Thanks to Calorify, the public now has access to a powerful tool to gain incredibly accurate insights into how their bodies work. But what do these results allow you to do? And what does applying them look like in practice?

To illustrate the transformative power of Calorify, let's delve into the personal story of Hari Mix, our founder and CEO. A dedicated lifelong athlete with a penchant for mountain climbing and hiking, Hari's journey predates the inception of Calorify.

Following the conclusion of his running career in 2009, Hari redirected his focus to mountain climbing, a passion he had long yearned to explore. Specifically drawn to high-altitude mountains exceeding 20,000 feet, Hari confronted the unique challenges posed by diminished oxygen levels at such elevations. At higher altitudes, the body undergoes significant metabolic changes, shifting from conventional fuel sources to prioritize glucose (carbs) over fatty acids (fats) and amino acids (proteins). Additionally, the gastrointestinal tract undergoes alterations, hindering nutrient absorption. This physiological stress, coupled with an increased heart rate to compensate for oxygen deficiency, makes high-altitude endeavors especially demanding on the metabolism.

In essence, hypoxia (lack of oxygen) induces stress, alters fuel utilization, and shifts the body's preferred fuel sources, leading to decreased hunger signals and reduced nutrient absorption. Weight loss becomes inevitable in this high-altitude scenario.

In Hari’s case, that weight loss was catastrophic during his high-altitude climbing events. In 2013 on Lhotse, the fourth highest mountain globally, he lost a staggering 25 pounds, the majority which was muscle and lean body mass (not fat stores).

So, a few years later, when planning his next big climb (Manaslu, the world’s eighth highest mountain), Hari wanted to do things differently. He wanted to avoid such catastrophic muscle losses that continue to set his adventures back.

Leveraging his background as a stable isotope scientist, he explored the doubly labeled water method. However, accessibility to such tests was limited until Calorify's inception. He reached out to Herman Pontzer, now Calorify’s Scientific Advisor, at Duke University to see if he could get tested over the course of this trip so that he could use the results to gain insights for future climbs.

Both eager to see the results, they laid out four distinct times that Hari would test so that they could track the changes his body went through at each stage of the trip:

California - during the week leading up to the trip, Hari was saving up his energy stores and remained rather sedentary.
Trek to the mountain - getting to the base of Manaslu took a few days, consisting of hiking 60-70 miles a day, popping in and out of the jungle, and tremendous amounts of elevation gain up and over a 17,000 foot pass.
Summit week - after a week of acclimatization, Hari’s push to the summit took four days to get to the camp beneath the summit of Manaslu.
On summit day - it took about 19 hours for Hari to reach the summit and get back to camp. He was only able to eat about 700 calories and lost a little under 4 pounds that day alone (not including water weight).

In order to prepare his body a bit better this time, Hari really focused on protein intake (protein shakes at camp were his favorite) and kept his body moving even on days he didn’t climb. He would take rocks from around camp and carry them around or do squats, just to remind his body to keep using those muscles.

Once back home, Hari sent off his samples to Duke for analysis. The results revealed a substantial improvement in muscle preservation, with only 3 pounds lost out of a total 11– a huge improvement from his time on Lhotse! At each stage of the trip, Hari’s energy expenditure increased drastically. On summit day, he burned right around 15,000 calories with a PAL of 8.77 (which, coincidentally is sustainable for exactly 1 day, according to the scientific literature).

Post-Manaslu, Hari continued refining his approach for energy-demanding multi-day trips. His focus shifted towards ensuring an adequate caloric intake, emphasizing calorie loading on specific days. His subsequent experiment on the Arizona Trail aimed to lose fat and gain muscle rather than experiencing overall weight loss.

Walking about 12 hours a day with a minimalist pack (he did make room for the testing supplies from his Calorify kit!), Hari meticulously planned his caloric intake based on Calorify's insights. Based on his previous tests, he guessed he’d be burning about 3,800 calories, meaning his minimum caloric intake to lose fat and gain muscle was right around 2,800 calories. He packed about 3,000 calories a day (including at least 100g of protein a day) in order to give himself a little buffer, putting him just below his ‘burn fat, build muscle’ zone, but above his recommended intake for max safe fat loss.

The, he got to it! He hiked 35-37 miles each day and his Calorify test came back saying he burned 3,739 calories a day that week. He didn’t see any significant body composition changes like he did in the past, meaning he executed his plan perfectly!

Why does Hari care about this weight loss so much? Can’t he just rebuild what he loses once he gets home?

Hari's emphasis on weight loss stems from the desire to preserve muscle, recognizing the challenges of rebuilding lean body mass as one ages. In his own words, "I just want to have fun. I want hiking to be sustainable and good for my body, not bad for it." For Hari, maintaining muscle is pivotal for the enjoyment and longevity of his adventures.

Hari founded Calorify to share this proven and precise method with the masses, allowing people everywhere to gain insights into one of the most important data points about your body: your metabolic rate.