RUNNING POWER: PARTICULARLY USEFUL FOR HILLS AND INTERVALS

Pace tells you how fast you're moving. Heart rate tells you how your body is responding. Running power adds another piece to the puzzle.

It's particularly useful for workouts where pace doesn't tell the whole story — hill repeats are a good example.

Imagine running the same hill workout every few weeks. By comparing your power, pace, and heart rate, you can see how your performance changes over time.

But there's an important point to remember: lower running power doesn't automatically mean better fitness.

Power isn't a metric you should simply try to minimize.

A much more useful indicator is your ability to produce more running performance at a similar physiological cost.

If you can run the same hill faster over time while maintaining a similar heart-rate response, that's a much more meaningful sign of improvement than the raw wattage number itself.

POST-WORKOUT HEART RATE: HOW QUICKLY DO YOU RECOVER?

It's also worth paying attention to what happens immediately after you stop running.

Once you finish recording a workout, your watch can continue monitoring your heart rate. On the Cheetah 2 Pro and Active 3 Premium, heart-rate monitoring continues for another three minutes, allowing you to see how quickly your heart rate falls after exercise.

This can be particularly useful when comparing harder workouts such as tempo runs, intervals, progression runs, or demanding cross-country sessions.

If your heart rate three minutes after a similar workout is lower than it was several weeks earlier, that may be a sign that your body is recovering more efficiently from the effort.

Again, consistency is key.

The most useful comparisons are between similar workouts performed under reasonably similar conditions.

LACTATE THRESHOLD: HOW FAST CAN YOU RUN BEFORE FATIGUE STARTS TO BUILD RAPIDLY?

One of the more advanced metrics available on the Cheetah 2 Pro and Active 3 Premium is lactate threshold.

In simple terms, your lactate threshold represents an intensity beyond which your body increasingly struggles to balance the production and clearance of lactate. As you push harder, fatigue begins to accumulate more rapidly, breathing becomes heavier, and maintaining the pace for an extended period becomes increasingly difficult.

So why does lactate threshold matter to runners?

Because training can shift your threshold toward a faster pace. In other words, you may eventually be able to run faster before reaching an intensity that becomes difficult to sustain for long.

The Cheetah 2 Pro and Active 3 Premium estimate this metric using data including pace and heart rate.

For example, imagine that earlier in your training you could run at 5:00 min/km at a heart rate of 170 bpm. After several weeks of consistent training, you can maintain 4:45 min/km at roughly the same heart rate.

That could be a sign that your fitness has improved and your lactate threshold has shifted to a faster pace.

RESTING HEART RATE: WHAT HAPPENS WHEN YOU'RE NOT RUNNING?

Not every useful fitness metric comes from your workouts.

Your resting heart rate can also provide valuable insight, particularly when it's monitored during sleep or overnight rest. Here, looking at the bigger picture is even more important. A single reading doesn't tell you much. A trend over several weeks can tell you considerably more.

If your resting heart rate remains stable and your average gradually decreases over time, that can be one indication that your body is adapting well to regular training.

But don't automatically interpret every change as a change in fitness.

A sudden increase in resting heart rate could be caused by poor sleep, stress, a hard training block, inadequate recovery, dehydration, or an illness that is just starting.

That's why it's better to look at several days or weeks rather than a single morning.

And an elevated resting heart rate can be just as useful a signal as a lower one. If it's consistently higher than normal for several days, it may be a sign that your body needs more time to recover.

Instead of adding another hard session, it may be smarter to take a rest day or keep the next workout easy.

Remember: fitness doesn't improve only while you're training. It also improves when you give your body enough time to adapt to the training you've done.

AND WHAT ABOUT VO₂MAX?

VO₂max, or maximal oxygen uptake, is probably one of the best-known fitness metrics.

In simple terms, it describes your body's ability to take in, transport, and use oxygen during maximal exercise. A higher VO₂max generally indicates greater aerobic potential, but it shouldn't be treated as a single definitive score for your overall fitness.

For a beginner, consistent running can lead to a noticeable increase in VO₂max. For a well-trained runner, changes may be much smaller — even while race performance continues to improve.

That's why it's best to treat VO₂max as one piece of the puzzle, rather than the ultimate measure of fitness.

It can be particularly interesting to track after a period of reduced training. Your VO₂max may drop after a break and then gradually recover as you return to regular workouts.

If you're training for a specific race, you can use this trend to see whether your VO₂max is moving back toward the level you reached at the end of the previous season.

CADENCE AND STRIDE LENGTH: DON’T CHASE A MAGIC NUMBER

Your watch can also provide insights into your running mechanics, including cadence and stride length. Cadence is the number of steps you take per minute, while stride length describes how far you travel with each step.

Both typically change as your running speed changes. But that doesn't mean there's one perfect cadence that every runner should aim for.

Your cadence is influenced by factors such as height, body proportions, running speed, technique, and training experience.

Rather than obsessing over hitting a particular number of steps per minute, it's often more useful to look at how your running mechanics change as you become tired.

Intervals are a good example.

Compare your cadence and stride length during the first few fast repetitions with those during the final ones. If you can maintain similar running mechanics toward the end of the session despite accumulating fatigue, that may indicate improved speed endurance.