How to Train for a High-Altitude Triathlon

Where Endurance Meets Elevation: How to Perform When Oxygen is Limited

Training for a triathlon is already a test of endurance, discipline, and resilience. Add high altitude to the mix, and you’re looking at an entirely different level of challenge—and opportunity. Whether you’re eyeing a race in the Colorado Rockies, the Alps, or the Andes, preparing properly can mean the difference between surviving and truly performing.

Why Altitude Matters

At high elevations (usually above 1,500–2,000 meters or 5,000–6,500 feet), the air contains less oxygen. That means your muscles—and your brain—receive less of the fuel they rely on for performance. This can lead to:

  • Reduced aerobic capacity (VO₂ max)

  • Faster onset of fatigue

  • Increased breathing and heart rate

  • Higher perceived exertion

  • Slower recovery

In short: what feels hard at sea level feels harder at altitude.

how to train for a high-altitude triathlon

Training Smart: Your Pre-Race Strategy

1. Get Acclimatized If You Can

If your schedule allows, arrive at race altitude 10–14 days before your event. This gives your body time to adjust to the lower oxygen levels, producing more red blood cells and improving oxygen transport.

Can’t spare the time? Research shows that arriving just a few hours before competition (the “fly‑in/fly‑out” strategy) is a plausible last‐resort, but it hasn’t been proven superior to arriving the evening before. In one controlled study, cyclists who arrived just hours before their 20 km time trial did not outperform those who flew in the night before—physiological measures (like sleep quality, ventilatory response, plasma volume) did not differ significantly between approaches.

2. Incorporate Altitude Simulation Into Your Training

If you’re training at sea level, simulated altitude training can help bridge the gap. Training in a hypoxic environment—like Altitude Athletic Training’s 10,000 ft facility in Toronto—can trigger beneficial adaptations that support endurance performance, such as:

  • Improved mitochondrial efficiency (more power output at the same effort)

  • Greater capillary density (better oxygen delivery to muscles)

  • Enhanced lactate buffering capacity (delay fatigue and recover faster)

  • Increased ventilatory response (more efficient breathing under stress)

Structured altitude exposure can improve aerobic efficiency and fatigue resistance, helping you perform better at elevation without needing to live in the mountains.

high-altitude triathlon training

3. Focus on Aerobic Efficiency

At altitude, you burn through your energy stores faster and accumulate fatigue more quickly. Training your aerobic system to be more efficient is key. Prioritize:

  • Long, steady-state efforts at Zone 2 (around 65–75% of max HR)

  • Brick workouts (bike-to-run) at controlled intensities

  • Strength training to improve muscular economy and injury resilience

4. Dial in Your Race Pace and Nutrition

Pacing at altitude is tricky—what feels sustainable early on can quickly lead to blow-up. Train with heart rate and perceived exertion as your guide, and use tools like lactate threshold or VO₂ testing to set accurate zones.

Also, hydration and fueling needs are higher at altitude. The air is drier, and sweat evaporates faster, increasing the risk of dehydration. Train your gut, know your fueling strategy, and stay on top of hydration.

triathlon training high-altitude

5. Don’t Neglect Recovery

Sleep quality often takes a hit at altitude. Combine that with the physiological stress of training and racing, and your body needs more time to recover. Use tools like:

  • Compression

  • Breathwork

  • Active recovery sessions

  • Low-intensity hypoxic training to promote adaptations without added strain

Training for a high-altitude triathlon isn’t just about working harder—it’s about working smarter. Prepare your body to adapt, get familiar with how altitude affects your pace and effort, and arrive confident that you’ve done everything possible to be ready.

Need help getting started with training or choosing the right strategy ? Book a consultation and let’s start planning your high-altitude triathlon training.

Leadville Trail 100: Three Tips to Master the Race Across the Sky

Taking on the Leadville Trail 100, the crown jewel of the Leadville Race Series, is no small feat. Known as the “Race Across the Sky,” this iconic ultramarathon challenges runners with its daunting altitude and rugged terrain. Whether you’re a seasoned ultrarunner or gearing up for your first 100-miler, following a solid Leadville 100 training plan is crucial for success. Here are three tips to help you conquer the Leadville Trail 100 and make the most of your Leadville 100 training.

 

 1. Train for Altitude

The Leadville Trail 100 is notorious for its high altitude, with much of the course sitting above 10,000 feet. The lack of oxygen at these elevations can significantly impact your performance, making altitude training a key component of any Leadville 100 training plan.

Tip: If possible, include altitude training in your Leadville 100 preparation. For those living at lower elevations, consider planning training trips to higher altitudes or incorporating altitude simulations. At Altitude Athletic, we provide simulated high-altitude conditions to help runners adapt to the demands of the Leadville Trail 100. Focus on building a strong aerobic base, improving your VO2 max, and practicing breathing techniques to enhance oxygen efficiency during the race.

Leadville trail 100

2. Use Heart Rate Monitoring to Guide Your Effort

Heart rate monitoring can be an invaluable tool in managing your effort throughout the Leadville Trail 100. With the high altitude and long distance, it’s easy to overexert yourself early in the race, which can lead to fatigue and a potential drop in performance later on.

Tip: Incorporate heart rate training into your Leadville 100 training plan to understand your optimal effort levels at different intensities and altitudes. On race day, use your heart rate monitor to stay within your target zones, especially in the early miles. This can help prevent you from going out too fast and ensure you conserve energy for the challenging sections later in the race. Monitoring your heart rate can also alert you to any signs of dehydration, overexertion, or altitude sickness, allowing you to adjust your pace or nutrition strategy accordingly.

 3. Master Your Nutrition and Hydration Strategy

Fueling your body properly during a 100-mile race is critical. The combination of long hours on your feet, high altitude, and unpredictable mountain weather means your body will be under immense stress. Proper nutrition and hydration can make or break your race.

Tip: During your training, experiment with different foods, gels, and hydration products to find out what works best for you. Your nutrition plan should include a balance of carbohydrates, proteins, and fats, with an emphasis on easily digestible foods that you can consume on the go. Hydration is equally important, especially considering the dry mountain air that can increase dehydration risk. Remember to include electrolytes to maintain balance, particularly sodium and potassium, which are vital in preventing cramps and maintaining energy levels. Dialing in your nutrition and hydration strategy ahead of time will help you avoid GI issues and energy bonks during the race.

 

Final Thoughts

The Leadville Trail 100 is a race that demands every ounce of your physical and mental strength. With a comprehensive Leadville 100 training plan that includes altitude acclimatization, heart rate monitoring, proper gear selection, and mental preparation, you can tackle this legendary race with confidence. By focusing on these key strategies, you’ll be well-prepared to conquer the Race Across the Sky and join the ranks of those who have triumphed in the Leadville Race Series.

 

Ready to train for the Leadville 100 or another ultramarathon? At Altitude Athletic, we specialize in preparing athletes for high-altitude races with our state-of-the-art training facility. Whether you’re looking to improve your altitude adaptation or fine-tune your race strategy, we’re here to help you reach new heights. Contact us today to learn more!

The Great Gender Gap – The Past, Present and Future of Women in Endurance Sports

WOMEN IN ENDURANCE SPORT. For many years, sport was considered to be only for men, as women’s physiology was viewed as being less efficient, weaker, and unable to push their bodies in the rigor of sport. Prior to the 1960’s, women were banned or restricted from longer running and endurance events. This is because they were considered “too fragile” for distance sport or even shorter Olympic events like the 400 and 800m sprints.

This began the era of mass participation of women in sports, and in the 1972 Olympics the first women’s 1500m was run. The same year, eight women “legally” ran the Boston marathon. By 1984 (only 35 years ago!) the first women’s Olympic marathon was sanctioned.

Women’s Participation Grows

In 2019, 45% of runners were women and in more local smaller city races, women tend to comprise over 50% of participants. Women’s participation in running and endurance sports has come leaps and bounds in just the last several decades, but only recently has science and psychology begun to identify some profound differences between the sexes. What exactly is it that differentiates women’s performance abilities from men?

Physiological Differences

It is generally accepted that women are smaller in stature. Women have more body fat, and less absolute muscle mass and fewer and smaller muscle fibers than men. As well, women have physiologically lower VO2 max numbers than men (the maximum amount of oxygen their bodies can utilize during high-intensity exercise), which is also sensible. In power-based activities, these differences are likely where the discrepancies primarily lie. Across the board, women’s distance running and cycling records among elite athletes are typically 10-12% slower than men, although with longer distances these patterns tend to change as we’ll discuss more later. It has also been seen that men have greater running velocity and can cover more distance in a set period of time. These differences are more profound in shorter, more powerful contexts like shuttle runs or sprints.

However, when it comes to longer, slower, or more submaximal effort events, women have some interesting advantages. Women have higher prevalence of slow-twitch muscle fibres which contract less quickly, but can contract consistently for very long periods of time. The hormone estrogen also seems to improve the oxidative capacity of muscles. This means greater oxygen update and improved recovery. Men however, tend to be able to have enhanced muscle growth due to higher level of testosterone – again, benefitting sports that favour power but potentially less valuable to low-and-slow type training and racing.

What Does This Mean?

So, when women train at the same intensity as men, they are able to adapt to the same degree, and in some circumstances even more effectively. As we’ve discussed, especially in distance events, women in endurance sports who focus on endurance training are able to become more metabolically efficient and run just as far as men. The science tells us that they should be as quick, but not so fast!

Female marathon runner competing

Go a Little Longer

When it comes to ultra-endurance events, women seem to have the upper hand. Many ultra-endurance race winners in unisex races are women – and not by a small margin. This past year, German cyclist Fiona Kolbinger raced 4000km through Europe and finished the Transcontinental Race 10 hours ahead of her closest male opponent. This past May, Katie Wright beat 40 men and six other women to win the Riverhead Backyard ReLaps Ultra-marathon in New Zealand, running almost non-stop for 30 hours. It seems that when the distances get longer, the women are rising to the top.

Why is this? Well, for all of the physiological science out there, there is only just recently a rise in the “biopsychosocial model” – which essentially looks at the mind-body connection and how the mind can affect boundaries within our deeply-entrenched biological systems. In excruciatingly-long distance races, athletes are working far under their maximal power for very long periods of time. Absolute strength and power is of less importance, and mental patience and grit hold much more water. Women also tend to be better at pacing themselves and “seeing further into the future” when moderating their early-race paces. Females also tend to use more emotion-focused coping mechanisms during the pain, fatigue, and sleep deprivation points in long races. Whether its experiences like childbirth or mental toughness from, well, life, it seems that this has given women a leg up when the going gets beyond difficult.

On the Whole…

Women have traditionally been seen as the physiologically “weaker sex” for many years. Culture and society has finally started challenging these norms, as women are now participating in events similar to men, and in some cases out-performing them. While it’s unlikely that women will naturally be lifting heavier weights than men or sprinting 100m faster than men, in longer races the gap is significantly lessened. Moreover, both genders need to remember that the power of the mind is probably the greatest tool of all, and with consistent training for both mind and body, great things can be achieved.

 

About the Author:

Lauren Roberts is a Registered Physiotherapist and Founder of The Running Physio in Toronto. For more information on her team, the clinic, and for more great blog articles, visit www.therunningphysio.ca

About Altitude Athletic Training: We are a group of coaches, scientists and fitness enthusiasts who empower members of all fitness levels to reach and exceed their athletic goals. All coaches have bachelor’s degrees in kinesiology (at minimum) and will help clients every step of the way. Learn more –>

Female athlete competing


References

Boston Athletic Association. (2019). 2019 Boston Marathon Statistics. Retrieved from https://registration.baa.org/2019/cf/Public/iframe_Statistics.htm

C. Baumgart, M. H. (2014). DIFFERENT ENDURANCE CHARACTERISTICS OF FEMALE AND MALE GERMAN SOCCER PLAYERS. Biology of Sport, 227-232.

Joyner, M. J. (2016). Physiological limits to endurance exercise performance: influence of sex. The Journal of Physiology.

K.M Haizlip, B. H. (2015). Sex-Based Differences in Skeletal Muscle Kinetics and Fiber-Type Composition. American Physiological Society, 30-39.

Williams, S. (2019, August 11). Are women better ultra-endurance athletes than men?