Speed Work Essentials: How to Structure Interval, Tempo, and VO₂ Max Workouts for Stronger Running

Last Update February, 17th 2026 by Etienne Durocher

If you run consistently, complete your long runs, and still feel like your pace never really improves, you’re not alone. Many intermediate runners and ultramarathoners accumulate mileage but avoid structured speed work, often because it feels intimidating, unnecessary, or risky.

Speed work isn’t about sprinting or ego-driven pace chasing. Done correctly, it improves running economy, strengthens your cardiovascular system, and teaches your body to handle discomfort more efficiently. Whether your goal is a faster half-marathon, a stronger marathon finish, or better durability in long-distance running, understanding how to structure interval, tempo, and VO₂ max workouts is essential.

In this guide, we’ll break down the three main types of speed work, explain how they apply to marathon and ultramarathon training, and show you how to integrate them safely into a busy training schedule.

What You Need to Know First

Speed work serves a purpose beyond running fast. Each type targets a different physiological system and should be used intentionally, not randomly.

At the intermediate level, speed work helps you:

• Improve efficiency at race pace

• Delay fatigue during long-distance running

• Maintain better form when tired

• Build mental tolerance to sustained effort

Before adding speed work, you should already have:

• A consistent weekly running routine

• A solid aerobic base

• At least one weekly long run

Speed sessions should support your training, not dominate it. One quality workout per week is enough for most intermediate runners. Ultramarathoners may rotate speed sessions every 7–14 days depending on race distance and terrain.

Understanding the Three Pillars of Speed Work

Interval Training: Teaching Your Body to Handle Stress

Intervals are short, controlled efforts run faster than race pace with recovery between repetitions. Their main goal is to improve oxygen uptake and neuromuscular efficiency.

Intervals are not about all-out effort. They should feel strong, controlled, and repeatable.

For marathon and half-marathon runners, intervals improve:

• Leg turnover

• Cardiovascular capacity

• Running economy at moderate paces

For ultramarathoners, intervals maintain speed and efficiency without excessive volume.

A typical interval session includes:

• A progressive warm-up

• Repeated efforts lasting 30 seconds to 5 minutes

• Full or near-full recovery

• A relaxed cool-down

Intervals work best early or mid-training cycle, not during peak fatigue weeks.

Tempo Runs: The Foundation of Race Strength

Tempo runs are sustained efforts at a “comfortably hard” intensity. You can speak short phrases but wouldn’t hold a conversation. This pace is critical for marathon and long-distance success.

Tempo training improves your lactate threshold, allowing you to run faster without accumulating excessive fatigue.

For intermediate runners, tempo runs:

• Build confidence at sustained effort

• Improve pacing awareness

• Translate directly to race performance

Tempo work can take several forms:

• Continuous tempo runs

• Broken tempos with short recovery

• Tempo segments within long runs

Unlike intervals, tempo runs are about control and patience, not speed.

VO₂ Max Workouts: Raising Your Aerobic Ceiling

VO₂ max sessions target your body’s ability to utilize oxygen efficiently. These workouts are shorter, more intense, and mentally demanding.

They are valuable but should be used sparingly, especially for ultramarathoners.

VO₂ max workouts:

• Improve cardiovascular efficiency

• Increase tolerance to high effort

• Support speed reserve for long races

These sessions typically involve:

• Efforts lasting 2–5 minutes

• Hard but controlled intensity

• Equal or slightly longer recovery

VO₂ max training is most effective when layered on top of a strong aerobic base, not as a replacement for it.

How to Structure Speed Work in a Real Training Week

Speed work must fit your overall training load. The biggest mistake runners make is stacking intensity on top of fatigue.

A balanced week often includes:

• One quality speed session

• One long run

• Easy aerobic runs between hard efforts

Speed workouts should never be placed the day after a long run. Recovery matters more than intensity.

For ultramarathoners, speed work is often reduced during high-volume phases and reintroduced during lower-mileage weeks to maintain sharpness.

If you want to better understand how speed work improves efficiency over time, I recommend reading:

• Running Economy: What It Is and How to Improve It

• Hill Training for Marathon Success

• Long Run Tips for Busy Runners

Each of these topics connects directly to how speed training supports long-distance performance without increasing injury risk. If you’re unsure how to integrate speed work into your own plan, personalized online coaching can help align workouts with your lifestyle and race goals.

Common Mistakes Runners Make With Speed Work

Many runners struggle with speed work not because it’s ineffective, but because it’s misused.

Common issues include:

• Running intervals too fast and compromising recovery

• Treating every tempo run like a race

• Adding speed sessions on top of already high fatigue

• Ignoring warm-up and cool-down phases

Speed work should feel purposeful, not punishing. The goal is adaptation, not exhaustion.

Practical Tips for Runners

• Introduce speed work gradually, starting with one session every 7–10 days

• Use perceived effort instead of pace, especially during fatigue or extreme weather

• Prioritize form, rhythm, and relaxation over chasing numbers

If you’re a very beginner runner or an advanced athlete preparing for a specific performance goal, speed work needs to be adjusted carefully. This is where individualized coaching makes a significant difference.

Final Thoughts

Speed work is not optional for runners who want to improve—it’s simply misunderstood. Interval training, tempo runs, and VO₂ max workouts each serve a specific purpose and, when structured correctly, make you a more efficient, resilient runner.

For intermediate runners and ultramarathoners, speed work doesn’t mean running harder every week. It means training smarter, respecting recovery, and building strength that carries into long-distance racing.

If you have questions about how to structure speed work within your marathon or ultramarathon training, feel free to comment below or reach out directly. Online coaching allows me to tailor workouts to your experience level, schedule, and long-term goals—wherever you’re training from in Canada or beyond.