When it comes to race day, every detail matters—especially your shoes. The Saucony Endorphin Pro 3 is a high-performance racing shoe designed for speed, but achieving your best time starts with getting the right fit. Whether you’re a seasoned marathoner or stepping into your first carbon-plated shoe, this size guide will help you understand how the Endorphin Pro 3 fits and how to choose the perfect size for your foot shape, stride, and goals.
Why Fit Matters for Racing Shoes
In a lightweight, responsive shoe like the Endorphin Pro 3, fit is performance. A shoe that’s too tight can cause blisters or black toenails over long distances, while a loose fit may lead to heel slippage or instability—especially with the curved rocker design and carbon plate. A dialed-in fit helps ensure:
- Efficient energy transfer
- Maximum comfort
- Reduced risk of injury
- Confidence in every stride
1. General Fit: True to Size or Not?
Most runners report that the Saucony Endorphin Pro 3 fits true to size, especially for those familiar with Saucony’s sizing in other models like the Endorphin Speed or Kinvara.
Fit Summary:
- Length: True to size
- Width: Slightly snug in the midfoot; secure heel lock
- Toe box: Moderately roomy—more accommodating than earlier versions
If you’re between sizes or wear thicker socks on race day, you might consider going half a size up, but for most, sticking to your regular running shoe size should work well.
2. Width Options: Is There a Wide Version?
As of now, the Endorphin Pro 3 is primarily offered in standard width (D for men, B for women). Runners with wider feet may find the forefoot snug but manageable due to the flexible mesh upper. If you typically wear wide-width shoes, consider trying a half size up or testing in-store before race day.
3. How the Fit Compares to Other Racing Shoes
Here’s how the Endorphin Pro 3 sizing compares to other popular carbon-plated racers:
| Shoe | Fit Compared to Pro 3 |
|---|---|
| Nike Vaporfly Next% 3 | Slightly longer/narrower toe box |
| Adidas Adizero Adios Pro 3 | Slightly roomier fit |
| ASICS Metaspeed Sky+ | Similar in length, snugger heel |
| New Balance FuelCell SC Elite | Wider in forefoot, softer fit |
Tip: If you’re switching from one of these, try your usual size first, but note where the shoe might feel tighter or more secure.
4. Try-On Tips Before Race Day
To find the ideal fit:
- Try them on later in the day when your feet are slightly swollen (like during a run).
- Wear your race-day socks for an accurate feel.
- Walk and jog a few steps to check for slippage or pressure points.
- Ensure at least a thumb’s width between your longest toe and the shoe’s end.
5. Break-In Period: Do You Need One?
The Endorphin Pro 3 is ready to race right out of the box, but a few shorter runs can help your foot adjust to the carbon plate and SPEEDROLL geometry.
Suggested break-in plan:
- 1 short tempo run (3–5 miles)
- 1 race-pace session or long run workout
- Race day
Avoid using them for daily training—they’re built for speed, not high-mileage durability.
6. Sizing for Orthotics or Insoles
If you use custom orthotics or thicker insoles, you may want to:
- Go up half a size to maintain a proper toe fit
- Remove the factory insole to create more space
- Ensure your insert doesn’t interfere with the carbon plate’s intended ride feel
7. Men’s and Women’s Size Conversion
If you need to convert between men’s and women’s sizes:
- Women’s to Men’s: Subtract 1.5 sizes
- Men’s to Women’s: Add 1.5 sizes
Example: Women’s 9 = Men’s 7.5
Always test the fit, as structural differences between men’s and women’s models may affect feel.
Final Thoughts: Lock In Your Race-Day Confidence
Choosing the right size in the Saucony Endorphin Pro 3 can mean the difference between a smooth, confident race and a painful slog. Most runners will find their regular size fits well, but considering your foot width, sock thickness, and insole needs can help fine-tune the perfect race-day feel.
Tip: Once you find the right fit, resist the urge to overtrain in them. Save them for when it counts—and let your shoes, and legs, fly.