Conor Dunne

The Sweet Spot of Struggle The mountains don't care about your excuses, they only care about your capacity to endure. In the world of high-performance cycling, Zone 3 training—often called **Tempo**—exists in the gray space between comfortable endurance and the searing pain of threshold work. It sits at roughly 75% to 90% of your Functional Threshold Power (FTP). While modern training trends often obsess over easy Zone 2 base miles or high-intensity intervals, the middle ground of Zone 3 provides a rugged, efficient path to grit and speed. Physiological Adaptations and Fiber Recruitment When you push into Zone 3, you trigger specific biological changes that easier rides simply cannot touch. This intensity targets **Type 2A muscle fibers**, the fast-twitch aerobic fibers that bridge the gap between pure endurance and explosive power. Expert Christy Stoshuk notes that this falls within the **heavy intensity domain**, located between lactate threshold one (LT1) and lactate threshold two (LT2). Training here forces these fibers to become more efficient, allowing you to hold steady, aggressive power for hours without your heart rate skyrocketing. It builds a "diesel engine" capable of churning through massive climbs and long-distance breakaway efforts. The Cardiovascular Edge for Recreational Athletes For those of us not riding in the pro peloton, Zone 3 might actually be the most effective use of limited time. Sports scientist Peter Leo explains that for recreational riders, Zone 3 efforts are often enough to max out **stroke volume** and cardiac output. This means you gain significant improvements in VO2 Max and general fitness without the soul-crushing fatigue of repeated maximal sprints. It is a high-yield investment for the time-poor athlete looking to prepare for events like the Atlas Mountain Race. Pacing the Knife Edge Precision is everything when you are operating in the tempo zone. If you push too hard, you slip into threshold territory, accumulating metabolic waste that ends your day early. Using heart rate as a cap is vital. As fatigue and heat set in, your heart rate will naturally drift upward even if your power remains constant. To stay in the effective zone, you must manage this drift. Peter Leo suggests allowing a delta of 5 to 10 beats per minute, but if you exceed that, you must either drop the power or end the set. Avoiding the Plateau Despite its benefits, Simon Jones warns that constant Zone 3 work can "flatten" a rider, particularly sprinters who need explosive top-end speed. To keep your edge, you need variety. Incorporate cadence changes—jumping from 60 RPM to 90 RPM—to keep the stimulus fresh. The goal is to build a foundation that is stable and powerful, giving you the mental and physical toughness to keep pressing the pedals when the wild world tries to slow you down.

The mountains usually demand everything you’ve got, but sometimes the most brutal peaks exist inside a digital landscape. For Naomi and Roosa, the challenge started not at a trailhead, but with a pile of boxes and a thirty-day deadline to prepare for a race on Zwift. The transition from casual pedaling to high-intensity interval training is a mountain of its own. It requires a specific kind of mental grit to stare at a screen while your lungs burn and sweat pools on the floor. They didn’t just learn to ride; they learned to suffer productively. Building the Machine and the Mind Setting up for a month of indoor training isn't just about the hardware, though the gear is impressive. Naomi worked with the Zwift Ride, a dedicated indoor bike that streamlines the connection between effort and avatar. Roosa opted for a more rugged approach, mounting her existing bike onto a smart trainer. This initial phase involves more than just tightening bolts; it’s about creating a dedicated space where you can push past your limits. You have to pair your sensors, calibrate your power, and accept that for the next month, your living room is a laboratory for performance. One of the most immediate shocks for any outdoor athlete moving inside is the heat. Without the natural wind resistance of the trail, your body temperature skyrockets. Naomi quickly discovered that towels and electrolytes are as vital as the bike itself. This is the raw reality of the ‘pain cave’—it’s an environment designed to strip away distractions until all that's left is your output in watts. The Brutality of the Benchmark Reality hits hard during the FTP Test. This isn't a leisurely ride; it’s a baseline for suffering. Functional Threshold Power (FTP) defines what you can sustain for an hour, and finding that number requires going to a very dark place. Roosa initially clocked in at 96 watts. It’s a humble starting point, but in the world of endurance sports, the numbers don't lie. They provide a target to destroy. As the training blocks progressed, the intensity ramped up into **VO2 Max** intervals. We're talking twenty seconds of max-effort sprinting followed by ten seconds of gasping for air. This is where most people quit. The digital hoops on the screen turn a threatening red, mocking your fatigue. Naomi found herself questioning the sanity of the process, yet she kept pedaling. That is the definition of mental toughness: continuing the effort when every instinct tells you to stop. Adversity and the Final Sprint Disaster struck Roosa outside the digital world when she suffered a crash that sent her over the handlebars. In the wild, a shoulder injury can end a season. But the beauty of the indoor setup is the ability to maintain some level of movement in a controlled environment. She had to navigate the psychological recovery alongside the physical, proving that an athlete’s resilience isn’t tied to a single race date but to the habit of showing up. Race day arrived with a frantic start. In Zwift, if you miss the initial surge, you're buried. Naomi found herself in the lead group, drafting behind a ‘ripped firefighter’ from France. This is where strategy meets pure brawn. You have to know when to sit in the wheels to save energy and when to burn your ‘Drafting Boost’ power-up. On the final kicker in the New York map, she threw down a massive sprint, closing gaps with a ferocity that surprised even her coach. She didn't take the win, but she found a gear she didn't know she possessed. The Lesson of the Dark Room Thirty days of digital climbing reveals a fundamental truth about fitness: the environment doesn't matter as much as the intent. Naomi realized she could squeeze in a high-intensity session in the dark, late at night, long after the trails would have been dangerous. The accessibility of indoor cycling removes the excuses that nature often provides. It forces you to look at your own data and own your progress. Pushing boundaries isn't always about standing on a literal summit. Sometimes, it’s about the sweat on your brow and the realization that you are stronger than your previous FTP test suggested. Nature is a great teacher, but the relentless data of a smart trainer is a master of accountability. Whether you're on a volcano circuit or a coastal trail, the struggle is where you find the athlete within.