HR vs speed ratio: What is it and how can you improve it?
The heart rate (HR) vs speed ratio is a powerful yet simple way to track how efficiently your body is working during your runs. By analysing the trends, you can gain valuable insights into your aerobic fitness, training effectiveness and overall running efficiency. Rather than focusing on individual numbers, it's best to look at the overall trend.
In this article we'll look at what the heart rate vs speed ratio tells you, why it's important and how you can use it to optimise your training.
HR vs speed ratio: What is it?
The heart rate (HR) vs speed ratio is a simple and useful way to monitor your heart rate and pace trends. It helps you understand how efficiently your body is working. The higher the HR vs speed ratio is, meaning the line is trending up, the faster you are running for the same heart rate.
Note: It is better to look at the overall trend line of your HR vs speed than to follow specific numbers. The heart rate is highly individual and so is HR vs speed ratio. It can only be compared in the context of the same runner, not to others.
What the trend line tells you
If the HR vs speed trend line is going up, you are running faster for the same heart rate, indicating that your aerobic fitness is improving.
If your HR vs speed trend line is going down, this may be a sign of fatigue or a weak aerobic foundation. Also, consider how your context may have influenced the trend and compare it with your feeling and perceived effort.
Why is it useful to follow the trend?
This metric serves multiple important purposes in training. It enables you to monitor fitness improvements, as consistent aerobic training should lead to a decreasing HR for the same pace over time.
You can also analyse how your heart rate responds to different speeds or intensities (for example, easy runs vs. tempo runs).
Additionally, it acts as an early warning system for overtraining. When the trend is going down, it might indicate fatigue, illness, or excessive training stress.
What factors affect the HR vs speed ratio?
Several factors influence the HR vs speed ratio. Your fitness level plays a fundamental role, as improved fitness typically results in a lower heart rate at a given speed. Environmental conditions such as temperature and humidity can increase heart rate. Dehydration or poor fueling can make your heart work harder. Stress levels, fatigue and a lack of recovery can all affect your HR vs speed ratio. Terrain variations such as hills or uneven surfaces also affect the ratio by requiring more effort to maintain the same speed. If you're doing a lot of speed work, this can lead to a higher HR to speed ratio. So it is important to compare trends within similar types of runs to get the most accurate insights.
How to use it in your training?
In KULG, you can monitor your ratio and follow the trend very easily.
The HR vs speed graph helps you understand how efficiently your body is working. You can track it by different time frames, such as monthly, quarterly, or annually. Or you can track it by types of running activities to check how the ratio varies across activities, such as tempo runs, long runs, and easy runs. With this, you get insights on your long-term running progress.
How can you improve your HR vs speed ratio?
Improving your HR vs speed ratio involves improving your running efficiency, aerobic capacity and overall fitness. The aim is to run faster at a lower heart rate, which signals improved cardiovascular and muscular efficiency.
7 tips to improve it
1. Build your aerobic base
The foundation of a strong HR vs speed ratio is a well-developed aerobic system.
Focus on low intensity running
Easy runs improve your body's ability to use oxygen efficiently and burn fat as fuel.
Run at a pace that keeps your heart rate in zone 2.
Consistency is key
Running regularly at this intensity for months at a time will significantly improve your performance.
2. Include speed work
While aerobic training is key, speed work helps improve running economy and neuromuscular coordination
Interval training:
Run shorter intervals (e.g., 400m–1km) at a hard pace with adequate recovery between reps.
Strides:
Add strides (20–30 seconds of fast running) after easy runs to improve your running form and efficiency.
Tempo runs:
Run at a comfortably hard pace (around your lactate threshold) for 20–40 minutes.
Progressive long runs:
Gradually increase your pace throughout your long runs to finish at or near your threshold pace.
3. Improve your running economy
Efficient movement reduces the energy cost of running, lowering your heart rate for a given pace.
Strength training:
Focus on exercises that build lower-body strength and power (e.g., squats, lunges, calf raises, and plyometrics).
Drills:
Incorporate running drills (e.g., high knees, A/B skips) to improve your stride mechanics.
4. Optimise your recovery
Recovery is essential for adapting to training and improving efficiency.
Prioritise sleep:
A good sleep allows your body to recover better.
Nutrition and hydration:
Eat a balanced diet rich in carbohydrates, protein, and healthy fats.
Stay hydrated before, during, and after runs.
Rest days and easy runs:
Include rest or active recovery days to avoid overtraining and ensure proper adaptation.
5. Train in different conditions
Running in varied environments helps your body adapt and improves your efficiency overall.
Hills:
Add hill training to strengthen your muscles and improve your cardiovascular system.
Heat acclimatisation:
Running in warmer conditions can improve your cardiovascular efficiency over time (BUT: Be cautious to avoid dehydration or heat exhaustion).
6. Cross-train
Other forms of aerobic exercise can strengthen your cardiovascular system while reducing the impact on your joints.
Cycling, swimming, or rowing:
These activities build aerobic fitness without the repetitive stress of running.
Yoga or mobility work:
Improves flexibility, posture, and breathing efficiency, all of which contribute to better running economy.
7. Last but not least: Stay patient
Improving your HR vs speed ratio takes time, especially if you're starting from a less developed aerobic base. Consistency over months or even years will give the best results.
Monitor your progress with KULG
KULG helps you train smarter and run better.
Monitoring your HR vs speed ratio can provide deep insights into your running progress, fitness improvements, and potential signs of overtraining. With KULG, you can easily track these trends over different timeframes and run types to ensure your training remains effective.
In KULG, we also provide you with colour hints in the Activity list to give you quick feedback on how your running activity is trending in terms of aerobic fitness or how efficiently your body is working.
HR vs speed quick hints
The darker the green dot, the stronger the relationship is in the context of your own training, meaning the faster you are running at the same heart rate.
The colour of the hint changes when you change the time frame or select a specific run type. This allows you to see your strongest runs within a specific time or when comparing specific run types (for example, when filtering out races).
Stay patient, train smart and let the data guide you on your journey to becoming a stronger, more efficient runner!
