Why Time-In-Range Is the New Gold Standard for Fitness Tracking
Traditional Fitness Metrics Aren’t Enough Anymore
Fitness professionals are obsessed with numbers: heart rate zones, calories burned, PRs, VO₂ max. But there’s a new metric on the rise, and it’s quietly becoming the most powerful way to track performance and progress: Time-In-Range (TIR).
This isn’t another trend; it’s a game-changer for how we coach, program, and measure results. It empowers us with a deeper understanding of our clients' metabolic responses.
What Is Time-In-Range (TIR)?
Time-In-Range (TIR) is a metric derived from Continuous Glucose Monitoring (CGM) that shows the percentage of time a person’s blood glucose stays within an optimal target range.
That target range is 70–140 mg/dL for most people, but it can be individualized.
A TIR of 80% means the client’s blood glucose was in the target range 80% of the time.
The higher the TIR, the better the energy stability, recovery, and performance potential.
Why TIR Beats Traditional Tracking Metrics
1. Heart rate and calories burned only tell part of the story.
They measure external effort, not internal response.
Two clients can burn the same calories but have wildly different metabolic reactions.
2. TIR reflects metabolic stability, not just intensity.
Staying in range means avoiding the spike-crash cycle that leads to fatigue, cravings, and poor recovery.
It correlates with improved energy availability and better training outcomes.
3. It gives coaches a valid performance indicator.
Clients with higher TIR consistently recover faster, have fewer energy dips, and hit their training goals sooner.
How Coaches Can Use TIR
Step 1: Track it with CGM.
Clients wear a CGM sensor for 2–4 weeks to establish a baseline.
Step 2: Identify the patterns.
What workouts knock them out of range?
Which meals stabilize or destabilize glucose?
Are sleep and stress impacting glucose control?
Step 3: Adjust training and fueling.
Shift workout types based on glucose trends.
Refine pre- and post-workout nutrition.
Address lifestyle factors affecting recovery.
Step 4: Re-check and optimize.
Use TIR as the gold standard for evaluating whether your adjustments are working.
Why This Matters for Every Fitness Professional
Your clients care about energy, results, and sustainability, and TIR connects the dots in a way they can understand.
When you can show your client that their time-in-range improved from 60% to 80%, you’re proving:
Their body is more metabolically stable
Their workouts and nutrition are working
They’re set up for long-term success
Get the Tool You Need to Start Coaching With TIR
Want to learn how to interpret CGM metrics like Time-In-Range with confidence?
Download the CGM Fitness Starter Bundle This resource will help you understand CGM data at a glance, so you can coach smarter, adjust faster, and deliver results your clients will rave about.
Time-In-Range is more than a number; it’s the new gold standard in fitness tracking.
It measures what matters most: metabolic stability and energy availability.
It allows you to personalize programs and eliminate the guesswork.
Don’t stay stuck on outdated metrics.
Grab the CGM Fitness Starter Bundle and use TIR to transform your coaching today.
