Racquet Plow-through, Stability, and Momentum

Racquet Plow-Through Tool

Incoming Ball Speed: Racquet Tip Speed: Choose Racquets To Compare
Racquet A Racquet B

2%
7%

-1%
1%

13%
15%

-1%
1%

-8%
-7%

9%
10%

25%
25%

9%
10%

-8%
-7%

18%
19%

36%
36%

18%
19%

48%
47%

— Test Point Locations —
Vertical: 16, 19, 21, 23, 25 in. from butt.
Horizontal: 0, -3, -2, 2, 3 in. from center.

Racquet A Summary
Location (Up / L & R)	Hitting weight (gm)	Location speed (mph)	Lost speed (mph)
16/0	287	42.1	22.1
19/+-2	155	47.7	38.9
19/0	214	47.7	30.4
21/+-3	100	51.9	56.3
21/+-2	129	51.9	47.2
21/0	168	51.9	39.1
23/+-2	106	55.9	56.6
23/0	131	55.9	48.8
25/0	103	60.0	58.5

Racquet B Summary
Location (Up / L & R)	Hitting weight (gm)	Location speed (mph)	Lost speed (mph)
16/0	283	42.1	22.1
19/+-2	155	47.7	38.7
19/0	213	47.7	30.4
21/+-3	102	51.9	55.3
21/+-2	131	51.9	46.7
21/0	170	51.9	38.7
23/+-2	109	55.9	55.4
23/0	135	55.9	47.5
25/0	108	60.0	55.7

Key Points

Plow-through is the percentage of racquet velocity at the impact location remaining the instant after impact.
The lower the number, the more velocity is lost, which means the racquet head (and your arm) experiences a larger deceleration during the 5ms of impact.
The higher the number, the more the racquet "plows through" the ball without slowing down as much.
A negative number means the racquet location is for a brief instant actually going backwards (due to twist, recoil, rotation), not just going slower!
More weight will increase plow-through and lower racquet speed lost (i.e., less shock).
Adding racquet speed increases plow-through but also increases speed lost (i.e., more shock).
Plow-through decreases from throat to tip and toward the periphery.
Plow-through quantifies what your arm might be feeling during impact.
See Also:

Explanation

What Is Plow-through?

Plow-through is a term of art to quantify and describe in everyday terms what happens to the racquet during impact. Plow-through has been defined as the percentage of pre-impact racquet velocity remaining immediately after impact. This velocity is calculated at the impact location. During impact the racquet hitting location decelerates by recoiling, twisting and rotating backward. These three decelerations can, just for a instant, decrease the hitting location to near zero or negative velocities. These results are calculated using the conservation of momentum formulas, where the racquet masses are the location hittingweight and the velocities are the impact location velocities. It is assumed that the player is not accelerating the racquet during the 5 ms of impact. Some of the relationships involved are these:

Power potential = 100 x (rebound speed / impact speed).
Impact speed = incident ball speed + impact location speed.
Bounce speed = power potential x impact speed.
Shot speed = impact location speed + location bounce speed.
Racquet power contribution = 100 x (location bounce speed / shot speed).
Plow-through = 100 x (post collision impact location speed / incident impact location speed)

Mass and mass distribution are the key racquet parameters determining plow-through. Plow-through quantifies what your arm/wrist/hand/shoulder might be feeling during impact.