Athletes & Celebrities

How Super-Runner Jax Mariash Trains

Ultra-athlete Jax Mariash’s workouts make your long run seem like an easy jog.

Zandy Mangold /

Think running a marathon is tough? Try logging upwards of 150 miles across some of the toughest terrain on the planet. That’s the type of challenge professional ultra-runner Jax Mariash likes to embrace. Last year, she became the first woman (and the fourth runner of all time) to complete the Grand Slam Plus, part of the grueling 4 Deserts Race Series. The races cross some of the hottest, windiest, driest, and coldest deserts in the world, including Africa’s Sahara Desert, China’s Gobi Desert, Chile’s Atacama Desert, and Antarctica; plus a “roving race” in the extremely humid climate of Sri Lanka. Mariash placed first among women in all the desert races and second in the Sri Lankan race.

Each race of the Grand Slam Plus stretches 155 miles and takes a week to run, with distances ranging from six to 50 miles a day, with one rest day. Support is limited: Runners must carry everything they need to survive in the elements, including food (about 2,000 calories per day), sleeping supplies, clothing, and safety equipment like blister kits, bandages, sunscreen, a utility knife, and head lamps. Race organizers will provide medical aid only in extreme cases, as well as a tent (shared with up to nine other runners each night), plus hot and cold water.