Saucony Endorphin Speed 3: A 100-Mile Long-Term Review

Introduction

Some shoes fall apart by the 100-mile mark. The Saucony Endorphin Speed 3 does the opposite: it has broken in with age and, if anything, feels better now than it did out of the box. After a full 100 miles of long runs and workouts, it has become a shoe that gets picked first, which is rare territory for a plated trainer at this mileage.

Who This Product Is For

The Endorphin Speed 3 suits runners who want a lightweight trainer that can double as a marathon race shoe. It is a good fit for anyone who wants a nylon plate that is less aggressive than the Endorphin Pro but still delivers noticeable bounce, and for runners who need just a touch more flexibility in a fast daily trainer.

Durability After 100 Miles

Durability is the first question at this mileage, and the answer here is encouraging. On a test pair known to chew through outsoles quickly, the wear at 100 miles looked like what would normally appear around 40 to 50 miles. Team members who saw the shoes guessed the mileage was closer to 40 or 50.

The full-length PowerRun PB foam has held up well too, and it has actually gotten a little more bouncy with mileage in a great way. The longer this shoe has been used, the better it has felt on long runs and workouts.

A Borderline Stable Neutral Ride

The Speed 2 could not handle very long mileage, and the Speed 1 had the same problem. The Speed 3 changes that. With the plate extending out to the sides and a wider outsole, Saucony has built a much more stable neutral platform, and it now handles long runs without issue.

The original assessment stands: this is now a borderline stable neutral shoe. It is not a true stability shoe, because the foam is soft, but it offers noticeably more support than its predecessors, which makes it a realistic option even for runners who had trouble with earlier versions.

Versatility for Training and Racing

This is a versatile ride that works for both training and racing. It took a little time for the PowerRun PB midsole to break in, but once it did, the shoe felt great at the end of long runs and made it easy to pick up the pace every time it was worn.

For runners who want a marathon shoe with a bit more flexibility than a super shoe like the Endorphin Pro, while still keeping a nylon plate and genuine bounce, the Speed 3 hits a comfortable middle ground.

Things to Consider Before Buying

The main consideration is the softness of the foam. If you need firm, structured stability, this is not that shoe. Also, the break-in period means early runs may not reflect how the shoe feels at 50 or 100 miles, so give it time before judging.

Buying Advice

At 100 miles, the Endorphin Speed 3 has proven itself as a durable, versatile, lightweight trainer that works for long runs, workouts, and racing alike. Runners who bounced off the Speed 1 or Speed 2 should give this version a real look, since the stability improvements are substantial.

If you want one shoe that can cover most of a training block and still show up on race day, this is a strong candidate.

Conclusion

The Saucony Endorphin Speed 3 gets better with mileage rather than worse. Strong outsole durability, a PowerRun PB midsole that grows more responsive over time, and a much more stable platform than previous versions make it one of the more versatile plated trainers available for both training and racing.