Saucony Endorphin Speed 4 vs Nike Zoom Fly 6

Which Running Shoe Is Better?

Products

Saucony Endorphin Speed 4
Nike Zoom Fly 6

Tested using Methodology v0.11

Updated May 12, 2026 02:27 PM

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Amazon

Tested using Methodology v0.11

Updated Apr 30, 2026 05:09 PM

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DicksSportingGoods.com
Saucony Endorphin Speed 4 Picture

Track

Nike Zoom Fly 6 Picture

Track

Our Verdict

Saucony Endorphin Speed 4

Nike Zoom Fly 6

The Nike Zoom Fly 6 and the Saucony Endorphin Speed 4 are both positioned as super trainers, designed to bridge the gap between daily trainers and race-day shoes. The Nike features a higher stack and full-length carbon plate, paired with a thin ZoomX top layer over firmer SR-02 foam, delivering a rockered, stable ride with decent cushioning. In contrast, the Saucony uses a plastic plate and PWRRUN PB foam, resulting in a ride that feels more energetic and responsive, but also less protective, especially under the heel. While both shoes can handle steady runs, up-tempo workouts, and occasional racing, the Saucony is lighter, bouncier, and better suited for runners who want a livelier, more grounded underfoot feel.

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Variants

  • Endorphin Speed 4 (Black - (Men - US 9))
  • Endorphin Speed 4 (Black - (Women - US 7))
  • Zoom Fly 6 (Black/Light Smoke Grey/White - (Men - US 9))
  • Zoom Fly 6 (Bright Crimson/Lime Blast/Mint Foam/Cave Purple - (Women - US 7))

Main Differences for
Marathon Racing

Threshold 

0.10

Marathon Racing 
 

7.8
7.7

Heel Stack Height 
 

37.2 mm
42.5 mm

Heel Compression Energy Return 
 

8.2
5.6

Forefoot Compression Energy Return 
 

8.4
7.5

Plate 
 

Plastic
Carbon Fiber

Full Comparison

Design

Weight  

6.8
6.5

Right Shoe Weight Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Right Shoe Weight Photo
Compare High-Res
Nike Zoom Fly 6 Right Shoe Weight Photo

Left Shoe Weight Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Left Shoe Weight Photo
Compare High-Res
Nike Zoom Fly 6 Left Shoe Weight Photo

Weight 
 

240.6 g (8.49 oz)
247.1 g (8.71 oz)

Stack Heights 
 

Stack Height Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Stack Height Photo
Compare High-Res
Nike Zoom Fly 6 Stack Height Photo

Heel Stack Height 
 

37.2 mm
42.5 mm

Forefoot Stack Height 
 

30.8 mm
32.8 mm

Heel-To-Toe Drop 
 

6.4 mm
9.7 mm

Advertised Heel-To-Toe Drop 
 

8.0 mm
8.0 mm

External Shape 
 

3D Model Full Shoe  

Preview 3D
Saucony Endorphin Speed 4 3D Model Full Shoe
Preview 3D
Nike Zoom Fly 6 3D Model Full Shoe

Outsole Heel Width 
 

92 mm (3.6")
84 mm (3.3")

Outsole Arch Width 
 

67 mm (2.6")
69 mm (2.7")

Outsole Forefoot Width 
 

113 mm (4.5")
112 mm (4.4")

Heel Width-To-Stack Ratio 
 

2.47
1.98

Forefoot Width-To-Stack Ratio 
 

3.67
3.41

Internal Shape 
 

3D Model Internal  

Preview 3D
Saucony Endorphin Speed 4 3D Model Internal
Preview 3D
Nike Zoom Fly 6 3D Model Internal

Internal Length 
 

275 mm (10.8")
275 mm (10.8")

Internal Heel Width 
 

59 mm (2.3")
61 mm (2.4")

Internal Forefoot Width 
 

91 mm (3.6")
87 mm (3.4")

Wide Sizing Available 
 

No
No

Forefoot Fit: Width 
 

8.9
9.0

Forefoot Width Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Forefoot Width Photo
Compare High-Res
Nike Zoom Fly 6 Forefoot Width Photo

Ball-Of-Foot TTS Deviation 
 

2.1 mm (0.084")
-2.7 mm (-0.105")

Toe TTS Deviation 
 

-3.2 mm (-0.126")
1.5 mm (0.059")

Forefoot Fit: Height 
 

7.8
7.8

Forefoot Height Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Forefoot Height Photo
Compare High-Res
Nike Zoom Fly 6 Forefoot Height Photo

Toe TTS Deviation 
 

-2.7 mm (-0.105")
-2.7 mm (-0.104")

Arch Fit: Width 
 

9.2
5.5

Arch Fit Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Arch Fit Photo
Compare High-Res
Nike Zoom Fly 6 Arch Fit Photo

Arch Width TTS Deviation 
 

-1.6 mm (-0.064")
-6.4 mm (-0.250")

Length Fit 
 

10
10

Toe Clearance Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Toe Clearance Photo
Compare High-Res
Nike Zoom Fly 6 Toe Clearance Photo

Heel Rocker Geometry 
 

8.6
7.6

Heel Rocker Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Heel Rocker Photo
Compare High-Res
Nike Zoom Fly 6 Heel Rocker Photo

Heel Spring 
 

22 mm (0.9")
25 mm (1.0")

Heel Apex Position 
 

64.2%
14.5%

Heel Rocker Angle 
 

24.1°
32.0°

Forefoot Rocker Geometry 
 

6.8
7.2

Forefoot Rocker Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Forefoot Rocker Photo
Compare High-Res
Nike Zoom Fly 6 Forefoot Rocker Photo

Toe Spring 
 

47 mm (1.9")
48 mm (1.9")

Toe Apex Position 
 

64.2%
61.8%

Forefoot Rocker Angle 
 

24.1°
24.6°

Other Features  

Other Features Photo 
 

Compare High-Res
Saucony Endorphin Speed 4 Other Features Photo
Compare High-Res
Nike Zoom Fly 6 Other Features Photo

Tongue Gusset Type 
 

Fully-gusseted
Fully-gusseted

Plate 
 

Plastic
Carbon Fiber
Performance

Heel Compression Energy Return 
 

8.2
5.6

Heel Compression Video  

Heel Energy Return  

 Preview Graph
Saucony Endorphin Speed 4 Heel Energy Return
 Preview Graph
Nike Zoom Fly 6 Heel Energy Return

Heel Energy Return 
 

82.1%
72.8%

Forefoot Compression Energy Return 
 

8.4
7.5

Forefoot Compression Video  

Forefoot Energy Return  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Energy Return
 Preview Graph
Nike Zoom Fly 6 Forefoot Energy Return

Forefoot Energy Return 
 

83.1%
78.2%

Heel Cushioning 
 

7.0
7.3

Heel Cushioning Picture 
 

Compare High-Res
Saucony Endorphin Speed 4 Heel Cushioning Picture
Compare High-Res
Nike Zoom Fly 6 Heel Cushioning Picture

Heel Cushioning  

 Preview Graph
Saucony Endorphin Speed 4 Heel Cushioning
 Preview Graph
Nike Zoom Fly 6 Heel Cushioning

Energy Absorbed At 550N 
 

2.85 J
3.50 J

Energy Absorbed At 1100N 
 

8.84 J
8.99 J

Energy Absorbed At 1900N 
 

15.67 J
14.93 J

Forefoot Cushioning 
 

6.7
7.2

Forefoot Cushioning Picture 
 

Compare High-Res
Saucony Endorphin Speed 4 Forefoot Cushioning Picture
Compare High-Res
Nike Zoom Fly 6 Forefoot Cushioning Picture

Forefoot Cushioning  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Cushioning
 Preview Graph
Nike Zoom Fly 6 Forefoot Cushioning

Energy Absorbed At 800N 
 

4.00 J
4.41 J

Energy Absorbed At 1300N 
 

7.23 J
7.70 J

Energy Absorbed At 2050N 
 

10.91 J
11.45 J

Heel Firmness 
 

5.8
5.9

Heel Firmness  

 Preview Graph
Saucony Endorphin Speed 4 Heel Firmness
 Preview Graph
Nike Zoom Fly 6 Heel Firmness

Firmness At 550N 
 

55.8 N/mm
51.7 N/mm

Firmness At 1100N 
 

106.9 N/mm
125.1 N/mm

Firmness At 1900N 
 

251.9 N/mm
266.8 N/mm

Forefoot Firmness 
 

8.3
8.2

Forefoot Firmness  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Firmness
 Preview Graph
Nike Zoom Fly 6 Forefoot Firmness

Firmness At 800N 
 

116.9 N/mm
110.8 N/mm

Firmness At 1300N 
 

223.9 N/mm
221.1 N/mm

Firmness At 2050N 
 

448.2 N/mm
432.4 N/mm

Forefoot Long Run Cushioning 
 

6.4
6.6

Forefoot Long Run Cushioning  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Long Run Cushioning
 Preview Graph
Nike Zoom Fly 6 Forefoot Long Run Cushioning

Energy Absorbed At 10km 
 

6.96 J
7.10 J

Energy Absorbed At 20km 
 

6.86 J
7.03 J

Energy Absorbed At 30km 
 

6.79 J
6.99 J

Energy Absorbed At 40km 
 

6.74 J
6.95 J

Rocker Stiffness 
 

7.4
8.2

Forefoot Rocker Stiffness Video  

Forefoot Rocker Stiffness Graph  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Rocker Stiffness Graph
 Preview Graph
Nike Zoom Fly 6 Forefoot Rocker Stiffness Graph

Force To Flatten The Rocker 
 

97 N
130 N

Forefoot Bending Energy Return 
 

7.7
7.0

Forefoot Bending Video  

Forefoot Bending Energy Return  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Bending Energy Return
 Preview Graph
Nike Zoom Fly 6 Forefoot Bending Energy Return

Forefoot Bending Energy Return 
 

69.7%
64.7%

Forefoot Bending Stiffness 
 

7.9
8.6

Forefoot Bending Resistance Picture 
 

Compare High-Res
Saucony Endorphin Speed 4 Forefoot Bending Resistance Picture
Compare High-Res
Nike Zoom Fly 6 Forefoot Bending Resistance Picture

Forefoot Bending Resistance  

 Preview Graph
Saucony Endorphin Speed 4 Forefoot Bending Resistance
 Preview Graph
Nike Zoom Fly 6 Forefoot Bending Resistance

Forefoot Bending Stiffness 
 

16.9 N/mm
24.1 N/mm

Forefoot Bending Force 
 

332 N
370 N

Saucony Endorphin Speed 4

Nike Zoom Fly 6

Comments

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Saucony Endorphin Speed 4 vs Nike Zoom Fly 6: Main Discussion

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