I love running, so I started building the tool I wanted to use

I love exercise, especially running. I want to get better at it and keep enjoying it for years to come. I’d like to run a little faster, but more than anything, I want exercise to remain part of my everyday life.

Loving running is one thing; sticking to a plan every week is another. Work runs late, something comes up, or I feel worn out on the day I finally have time. Sometimes the calendar says to run, but rest feels like the right choice.

I needed a tool to help me decide what to do next, based on the time I had and how I felt. I had a goal. I wanted to keep working toward it in a way that fit my life.

“What if I built something like that for myself?”

That is where RUNTINE began. I am still building the running tools I want to use, one at a time.

The questions that came after making a plan

Running keeps giving me new questions. Once I have a goal, I look up how much to run. Once I have a plan, I wonder how to fit it into my week.

I felt especially unsure after missing a session. Could I simply skip an easy run? Could I move a missed weekend long run into the following week? Even when I understood the general advice, applying it to my own calendar took more thought.

Suppose I miss Thursday's workout and have a long run planned for Saturday. Moving the missed session to Friday fills the empty space. But whether there is enough recovery between those workouts is a separate question.

That was the problem I wanted to explore. I wanted to think beyond whether one workout was completed and consider the next one too.

I started with one question I actually had

A feature list grows quickly. I want to track race goals, review recent runs and organize training more easily. But trying to include everything at once can make it harder to see when each feature would actually help.

So I chose a smaller first question: “I missed this workout. What should I do now?” The missed workout rescheduler grew from that question.

Choose the kind of workout you missed, your next key workout date and the days you can run this week. The tool also asks about pain or unusual symptoms. I kept the questions short: if a quick check required too many inputs, I would be reluctant to use it myself.

The web tool works without signing in, and calculations based on your inputs happen in the browser. It does not retrieve your training history or rebuild your entire plan. It is a simple way to review this week's options.

I wanted to understand the reason behind a suggestion

For a tool I would use myself, “run on this day” was not enough. I wanted to know why moving a session might be reasonable, or why skipping it might be better. So the result includes an explanation.

If you miss an easy run and have enough room before your next key session, the tool suggests a short, comfortable run on another day. If you miss a hard session or long run and the next important workout is too close, it suggests skipping the missed one. It also explains not to add the missed distance to the next session.

A few inputs cannot capture everything about your health or schedule. You still need to consider whether you’ll have recovered by the suggested day and whether you have other exercise planned. I want the explanation to support your own judgment.

If you report pain or unusual symptoms, the tool does not recommend a workout date. As much as I love running, I did not want it to prioritize checking off workouts over listening to your body. In that situation, checking symptoms comes first.

A worked example you can reproduce

Consider a hypothetical Monday: Tuesday is your only available day, your next key workout is Thursday, and you report no pain or unusual symptoms.

These are the tool's conservative scheduling rules, not a claim that a fixed number of days guarantees recovery. It only considers the available dates you enter within the next seven calendar days and the next key workout. It cannot see other sessions, sleep, illness or your training history. If several dates fit, it chooses the earliest one.

You can try the same inputs in the free rescheduler. This example demonstrates its behavior; it is not a report of a user's training outcome or a personalized training prescription.

I picture the moment when I will use each feature

While building a feature, I often wonder what else to show or how much to explain. I picture being about to head out for a run, or just returning from one. Would I want to read this then? How many taps would it take to find what I need?

That is why changing an input in the rescheduler updates the result immediately. I wanted to try different options and see the suggestions without filling out and submitting a form each time.

These are the details I want to keep improving in RUNTINE: how easily I can plan around my schedule, whether my workout logs help me decide what to do next, and whether proposed plan changes are clear. Whenever I add a feature, I picture myself using it.

A tool I started for myself, made to be shared

At first, I simply wanted to feel less lost and keep doing an activity I enjoy. As I built it, I hoped it might also help runners with similar questions. Our lives differ, but many of us love exercise while finding it difficult to follow every plan.

There is still plenty I want to build and improve. I am learning more about running as I develop RUNTINE. Here, I plan to share the questions I had, the features I actually made and the ways my thinking changed along the way.

After a missed workout, I want the next step to feel manageable. I hope to make a tool that keeps helping me—and other runners—fit running into everyday life.