Calibrate: a wearable + app for champions


Most fitness trackers and training apps are designed for the general population. Performance athletes are edge cases making these other trackers essentially useless for their training and fitness needs. 

Calibrate is designed for these high performance athletes – the marathon runners, pro cyclists, Olympians – who are not often designed for in the fitness tracking world. Using a combination of a continuous wear wristband and mobile app, athletes are provided deep insights regarding their resting heart rate, heart rate variability, sleep, and caloric needs. With this detailed feedback, they can work with their coach and on their own to train for optimal, athletic success. 

key skills
design research, UI,
prototyping, usability testing

Sketch, Principle, Whimsical

Kate Rutter

8 weeks


research, insights, hmw 



Female, performance athletes - those training for specific sports and goals instead of just general fitness

Most fitness trackers and training apps are for the general population - performance athletes are edge cases. Female performance athletes are especially unique - menstruation greatly impacts training, racing, and recovery.

Using scoring methods that encompasses heart rate variability (HRV)*, resting heart rate (RHR), sleep and the menstrual cycle, scores determine how close an athlete is to her peak performance.

Using these metrics enables women to understand their recovery level, a useful tool in injury prevention and a predictor of optimal performance. 

*HRV, also known as heart rate variability is the naturally occurring irregularity of our heartbeat. For example, your heart may beat 60 times in a minute, but the time between those beats isn't equal. Exercise physiologists have uncovered that HRV is a powerful tool in determining optimized training loads, especially in response to physiological stress.



Research Process Overview

Secondary research exploration

  • Existing fitness trackers + wearables

  • Existing training software + associated devices

  • Physiologic markers including RHR, HRV, sleep, nutrition, hormones, menstruation

  • Read studies validating the impact of measuring recovery utilizing physiologic markers and resulting improvements in athletic performance


  • professional cyclists

  • amateur cyclists

  • CrossFit competitors

  • amateur triathletes

You never know if you’re not doing enough, or too much...eating too much, not enough, there are a lot of things that are hard to navigate.
— B. G.
If the body is happy, I can be a little more at ease.
— L. C.


Research Synthesis: Insights

insight 1.png
insight 2.png
insight 3.png
insight 4.png


How Might We...




After two distinct rounds of interviewing real athletes, creating insights, and defining the HMW, here is a key persona: 


functional + visual design


The 2 Components

The Wristband


The App


Initial Sketches + Wireframes


Read more about my process of simplifying Calibrate here.


Main Dash


HRV Weekly Trends


Defining HRV


Sleep Weekly Trends


Resting Heart Rate Dash


Sleep Time


Maps: Ecosystem + System Maps

The full system flow can be seen here.



Usability Testing 

Users came from two places. First, I went to a CrossFit gym and asked women their fitness goals, inviting those who are training for competitions to participate. Second, since I have a large athlete network myself, I had my athlete friends ask their elite athlete friends if they were willing to participate.

I had the participants perform a series of tasks including...

  • You just woke up and want to see what your resting heart rate (RHR) is. Can you walk me through how you will find this info?

  • It's your first time using this app and you've never heard of HRV. How will you find the definition of this in the app?

  • You want to share your data with your coach. Show me how you think you will add her/him?

  • You want to compare sleep across weeks. How will you find this?

A Handful of Takeaways

  • What section of the app am I in?

    • Need for better labeling

  • Donut circles well recieved but additional desire for a name of each state

    • Led to generating names for each recovery phase

  • Preference for a focus on how much actual sleep

    • And curious to know how much more was needed

  • Clicking the dots on sleep graph for each day of week not obvious

    • Eliminated this function - simplified graph

Positive Validation

Having my cycle day front and center would be an interesting element to pay attention to while I train.
— A. T.
When can I buy this?
— L. C.
I want this! Being able to observe my recovery patterns would be extremely helpful.
— K. C.
I’d love to be able to dig into all this data.
— E. G.

Testing + Prototyping on Myself

I created a rough rating system incorporating numerous factors to see how tracking these elements would effect my everyday levels of rest, recovery, and training.



Final Concepts

  • I chose colors that are feminine, without being cliche.

  • Since this is a data heavy app, I opted for a clean, minimal UI to keep the focus on the data.

  • I opted for high contrast colors that looked like they were almost glowing to show distinctions across recovery and sleep levels and other notable changes.


Main Dash

HRV Trends Screen

Weekly Sleep Time