How hard should a tempo run feel?

A tempo run should feel "comfortably hard," where talking is difficult but not impossible, typically falling at 7-8 on a perceived exertion scale of 1-10.

What is the main physiological goal of a tempo run?

The primary goal of a tempo run is to elevate your lactate threshold, training your body to become more efficient at clearing lactate and tolerating higher levels of it.

What are the benefits of incorporating tempo runs into training?

Tempo runs improve endurance, increase lactate threshold, enhance mental toughness, and lead to better race pacing and more efficient running economy.

How often should tempo runs be incorporated into a training schedule?

For most runners, one tempo run per week or every other week is sufficient to avoid overtraining, always including a warm-up and cool-down.

How can I measure the correct intensity for a tempo run?

You can measure intensity using perceived exertion (RPE 7-8), pace (10-20 seconds slower than 10k pace), heart rate (85-90% MHR), or the talk test (short, broken sentences).

Are tempo runs hard?

Tempo runs are designed to be challenging but sustainable, operating at an intensity often described as "comfortably hard" – a deliberate effort that pushes your physiological limits without leading to immediate exhaustion.

Understanding the "Hardness" of Tempo Runs

The perceived difficulty of a tempo run is subjective, yet objectively, it's meant to be a significant cardiovascular and muscular effort. Unlike an easy recovery run where you can hold a full conversation, a tempo run requires a focused, sustained exertion that makes talking difficult, but not impossible. It's a sweet spot of discomfort that, when executed correctly, yields substantial physiological benefits. For a beginner, this effort might feel intensely hard, while an experienced runner might find it a familiar, manageable challenge.

What Exactly Is a Tempo Run?

A tempo run is a sustained effort run performed at a pace that is challenging but can be maintained for a significant duration, typically 20-60 minutes (including warm-up and cool-down). Its primary physiological target is to train your body at or around your lactate threshold (LT). This is the point at which lactate begins to accumulate in the blood at a rate faster than it can be cleared.

The Physiology Behind the Effort: Lactate Threshold Training

The "hardness" of a tempo run stems directly from its objective: to elevate your lactate threshold.

Lactate Production: During intense exercise, your muscles produce lactate as a byproduct of anaerobic metabolism.
Lactate Clearance: Your body has mechanisms to clear this lactate and convert it back into energy.
Lactate Threshold: At a certain intensity, lactate production surpasses lactate clearance, leading to a rapid accumulation that causes muscle fatigue and forces a reduction in pace. Tempo runs train your body to become more efficient at clearing lactate and to tolerate higher levels of it, pushing back that threshold. This adaptation makes you able to sustain faster paces for longer durations. The effort feels hard because you are operating at the edge of this physiological balance.

Measuring Your Tempo Run Intensity

To ensure you're hitting the "comfortably hard" zone without overdoing it, use a combination of these methods:

Perceived Exertion (RPE): On a scale of 1 to 10 (1 being very easy, 10 being maximal effort), a tempo run typically falls between 7 and 8. You should feel a strong effort, but not an all-out sprint.
Pace: This is generally 10-20 seconds per mile slower than your current 10k race pace, or approximately 25-30 seconds per mile faster than your marathon pace. It's a pace you could theoretically maintain for about an hour in a race setting.
Heart Rate: Aim for 85-90% of your maximum heart rate (MHR), or approximately 80-85% of your heart rate reserve (HRR). This range indicates you are working aerobically but close to your anaerobic threshold.
Talk Test: You should be able to speak in short, broken sentences, but not carry on a full conversation. If you can talk easily, you're not going hard enough. If you can't utter more than a word or two, you're likely going too hard.

Why Tempo Runs Are So Beneficial

Despite their challenging nature, tempo runs are a cornerstone of effective running training due to several key benefits:

Improved Endurance: By training your body to sustain higher intensities, you build overall aerobic capacity.
Increased Lactate Threshold: This is the primary benefit, allowing you to run faster for longer before fatigue sets in.
Enhanced Mental Toughness: Consistently pushing through the "comfortably hard" zone builds mental resilience crucial for racing.
Better Race Pacing: Tempo runs teach you to recognize and maintain an optimal race pace, preventing you from starting too fast or fading too early.
More Efficient Running Economy: Your body learns to use oxygen more efficiently at higher speeds.

Common Mistakes That Make Tempo Runs "Too Hard"

While tempo runs are meant to be hard, they shouldn't be agonizing. Several common errors can push them beyond their intended "comfortably hard" zone:

Starting Too Fast: The most frequent mistake. A tempo run should have a gradual build-up, not a sprint from the start.
Confusing Tempo with Interval Training: Tempo runs are sustained; intervals involve short bursts of maximal effort followed by full recovery. Mixing these up leads to unsustainable effort.
Insufficient Warm-up: Skipping a proper warm-up means your body isn't ready for the demands, making the effort feel much harder.
Running on Tired Legs: Attempting a tempo run after insufficient recovery from previous hard workouts can lead to overtraining and injury.
Ignoring the Talk Test/RPE: Relying solely on pace, especially on hilly or windy days, can lead to overexertion. Always cross-reference with how you feel.

Incorporating Tempo Runs into Your Training

Frequency: For most runners, one tempo run per week or every other week is sufficient. More frequent tempo runs can lead to overtraining.
Progression: Start with shorter durations (e.g., 15-20 minutes at tempo pace) and gradually increase the length of the tempo segment as your fitness improves.
Workout Structure: Always begin with a 10-15 minute easy warm-up and end with a 10-15 minute easy cool-down. The tempo segment is sandwiched in between.
Examples:
- Classic Tempo: 10-15 min warm-up, 20-30 min at tempo pace, 10-15 min cool-down.
- Tempo Intervals (Cruise Intervals): 10-15 min warm-up, 3-5 x 8-10 min at tempo pace with 1-2 min easy jogging recovery between efforts, 10-15 min cool-down. This allows for slightly longer time at tempo effort with brief recovery.

Conclusion: The Rewarding Challenge

Yes, tempo runs are hard. They are intentionally designed to push your physiological boundaries, demanding a sustained, focused effort that sits squarely in the "comfortably hard" zone. This difficulty, however, is precisely what makes them one of the most effective tools for improving running performance. By consistently engaging with this challenging effort, you train your body to run faster, for longer, and with greater efficiency, ultimately transforming your running potential. Embrace the challenge, respect the intensity, and reap the significant rewards.

Tempo Runs: Understanding Their Challenge, Benefits, and How to Integrate Them