> ## Documentation Index
> Fetch the complete documentation index at: https://docs.uplift.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Tennis Overhand Serve: Normative Ranges

> Full percentile reference tables (5th–95th) for tennis overhand serve metrics, broken out by competition level.

This page collects the complete normative reference tables for the tennis overhand serve — the full 5th–95th percentile range for each competition level, drawn from the same normative dataset that backs the [Normative Ranges](/biomechanics/normative-ranges) guide. See that page for how to interpret these tables.

Each competition-level dataset was built by pooling all valid serve sessions per athlete, selecting the single session closest to that athlete's overall average across all metrics, then re-analyzing with the latest biomechanical analysis software and removing sessions that failed Uplift's quality assurance tests. Unlike baseball, the tennis dataset currently only supports **Youth**, **Professional**, and **Broad (All Levels)** populations — College and High School brackets are not yet available.

## Youth Sample

### Kinematic Sequence – Forward (Serve Direction) Angular Velocities & Speedups

Prefer higher velocities and speedup factors for better performance.

| Variable                                                                                                                   |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units |
| -------------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Peak Torso Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-torso-forward-angular-velocity)         |  147 |  160 |  184 |  206 |  234 |  256 |  264 | deg/s |
| [Peak Upper Arm Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-upper-arm-forward-angular-velocity) |  653 |  680 |  805 |  887 |  997 | 1073 | 1120 | deg/s |
| [Peak Forearm Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-forearm-forward-angular-velocity)     |  746 |  776 |  858 |  976 | 1101 | 1212 | 1256 | deg/s |
| [Forward Trunk Arm Speedup](/biomechanics/activities/tennis/metrics/forward-trunk-arm-speedup)                             | 3.22 | 3.38 | 3.80 | 4.32 | 4.91 | 5.45 | 5.88 | ratio |
| [Forward Upper Arm Forearm Speedup](/biomechanics/activities/tennis/metrics/forward-upper-arm-forearm-speedup)             | 0.80 | 0.85 | 0.97 | 1.09 | 1.25 | 1.41 | 1.54 | ratio |

### Kinematic Sequence – Twist Angular Velocities & Speedups

Prefer higher velocities and speedup factors for better performance.

| Variable                                                                                                               |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units |
| ---------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Peak Pelvis Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-pelvis-twist-angular-velocity)       |  190 |  215 |  284 |  366 |  446 |  495 |  512 | deg/s |
| [Peak Torso Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-torso-twist-angular-velocity)         |  253 |  282 |  335 |  379 |  417 |  450 |  473 | deg/s |
| [Peak Upper Arm Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-upper-arm-twist-angular-velocity) |  214 |  270 |  333 |  411 |  495 |  566 |  628 | deg/s |
| [Twist Trunk Arm Speedup](/biomechanics/activities/tennis/metrics/twist-trunk-arm-speedup)                             | 0.60 | 0.71 | 0.89 | 1.10 | 1.35 | 1.60 | 1.75 | ratio |
| [Twist Pelvis Torso Speedup](/biomechanics/activities/tennis/metrics/twist-pelvis-torso-speedup)                       | 0.70 | 0.78 | 0.87 | 1.05 | 1.26 | 1.58 | 1.71 | ratio |

### Loading Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                               |   5%   |   10%  |   25%  |   50%  |   75%  |   90%  |   95%  | Units    |
| ---------------------------------------------------------------------------------------------------------------------- | :----: | :----: | :----: | :----: | :----: | :----: | :----: | -------- |
| [Loading Phase Max Knee Flexion Front Leg](/biomechanics/activities/tennis/metrics/loading-phase-knee-flexion)         |   50   |   53   |   59   |   68   |   78   |   85   |   89   | deg      |
| [Loading Phase Max Knee Flexion Back Leg](/biomechanics/activities/tennis/metrics/loading-phase-knee-flexion)          |   42   |   53   |   65   |   70   |   81   |   87   |   93   | deg      |
| [Loading Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/loading-phase-trunk-tilt)                           |   -29  |   -25  |   -21  |   -15  |   -11  |   -6   |   -1   | deg      |
| [Loading Phase Pelvis Tilt](/biomechanics/activities/tennis/metrics/loading-phase-pelvis-tilt)                         |   -9   |   -8   |   -6   |   -3   |    0   |    1   |    2   | deg      |
| [Loading Phase Shoulder Hip Separation](/biomechanics/activities/tennis/metrics/loading-phase-shoulder-hip-separation) |    0   |    3   |   11   |   19   |   29   |   35   |   40   | deg      |
| [Loading Phase Ball Release Angle](/biomechanics/activities/tennis/metrics/loading-phase-ball-release-angle)           |   76   |   95   |   105  |   122  |   137  |   152  |   156  | deg      |
| [Trunk Coil](/biomechanics/activities/tennis/metrics/trunk-coil)                                                       |  -142  |  -138  |  -130  |  -119  |  -111  |  -104  |   -99  | deg      |
| [Pelvis Coil](/biomechanics/activities/tennis/metrics/pelvis-coil)                                                     |  -132  |  -129  |  -122  |  -113  |  -108  |   -99  |   -87  | deg      |
| [Trunk Stretch](/biomechanics/activities/tennis/metrics/trunk-stretch)                                                 |   124  |   137  |   151  |   160  |   171  |   181  |   186  | deg      |
| [Pelvis Stretch](/biomechanics/activities/tennis/metrics/pelvis-stretch)                                               |   86   |   102  |   118  |   130  |   144  |   158  |   164  | deg      |
| [Release Phase Elbow Angle](/biomechanics/activities/tennis/metrics/release-phase-elbow-angle)                         |    1   |    2   |    7   |   19   |   27   |   40   |   44   | deg      |
| [Max Front Knee Valgus (Normalized)](/biomechanics/activities/tennis/metrics/max-front-knee-valgus)                    | -0.041 | -0.036 | -0.029 | -0.021 | -0.016 | -0.009 | -0.006 | × height |
| [Max Back Knee Valgus (Normalized)](/biomechanics/activities/tennis/metrics/max-back-knee-valgus)                      | -0.023 | -0.021 | -0.017 | -0.011 | -0.006 | -0.004 | -0.003 | × height |

### Cocking and Acceleration Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                                                       |  5% | 10% |  25% |  50% |  75% |  90% |  95% | Units |
| ---------------------------------------------------------------------------------------------------------------------------------------------- | :-: | :-: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Cocking Phase Max Shoulder External Rotation](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-external-rotation)               | 154 | 163 |  170 |  179 |  188 |  194 |  199 | deg   |
| [Cocking Phase Shoulder Hyperangulation](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-hyperangulation)                       | 136 | 141 |  146 |  155 |  163 |  172 |  178 | deg   |
| [Cocking Phase Max X Factor](/biomechanics/activities/tennis/metrics/cocking-phase-max-x-factor)                                               |  -6 |  0  |   9  |  17  |  26  |  35  |  38  | deg   |
| [Cocking Phase Shoulder Horizontal Abduction](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-horizontal-abduction)             |  61 |  68 |  75  |  87  |  98  |  102 |  104 | deg   |
| [Acceleration Phase Max Knee Extension Velocity Front Leg](/biomechanics/activities/tennis/metrics/acceleration-phase-knee-extension-velocity) | 238 | 269 |  298 |  345 |  381 |  414 |  431 | deg/s |
| [Acceleration Phase Max Knee Extension Velocity Back Leg](/biomechanics/activities/tennis/metrics/acceleration-phase-knee-extension-velocity)  | 182 | 223 |  304 |  351 |  394 |  420 |  433 | deg/s |
| [Acceleration Phase Max Elbow Extension Velocity](/biomechanics/activities/tennis/metrics/acceleration-phase-elbow-extension-velocity)         | 852 | 920 | 1037 | 1155 | 1251 | 1329 | 1422 | deg/s |

### Contact Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                                     |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units       |
| ---------------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----------- |
| [Contact Phase Elbow Flexion](/biomechanics/activities/tennis/metrics/contact-phase-elbow-flexion)                           |  29  |  31  |  39  |  46  |  53  |  60  |  63  | deg         |
| [Contact Phase Shoulder Abduction](/biomechanics/activities/tennis/metrics/contact-phase-shoulder-abduction)                 |  103 |  106 |  113 |  123 |  129 |  135 |  139 | deg         |
| [Contact Phase X Factor](/biomechanics/activities/tennis/metrics/contact-phase-x-factor)                                     |  -8  |  -5  |  -1  |   3  |   8  |  14  |  16  | deg         |
| [Contact Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/contact-phase-trunk-tilt)                                 |  29  |  31  |  34  |  38  |  42  |  46  |  47  | deg         |
| [Time to Contact](/biomechanics/activities/tennis/metrics/time-to-contact)                                                   | 0.60 | 0.72 | 0.80 | 0.91 | 1.00 | 1.11 | 1.17 | s           |
| [Contact Phase Trunk Flexion](/biomechanics/activities/tennis/metrics/contact-phase-trunk-flexion)                           |   1  |   4  |  10  |  14  |  20  |  30  |  32  | deg         |
| [Contact Phase Trunk Rotation](/biomechanics/activities/tennis/metrics/contact-phase-trunk-rotation)                         |  -40 |  -38 |  -33 |  -24 |  -12 |  -5  |  -2  | deg         |
| [Contact Phase Pelvis Rotation](/biomechanics/activities/tennis/metrics/contact-phase-pelvis-rotation)                       |  -43 |  -42 |  -38 |  -33 |  -25 |  -19 |  -14 | deg         |
| [Contact Phase Wrist Height (Normalized)](/biomechanics/activities/tennis/metrics/contact-phase-wrist-height-normalized)     | 1.14 | 1.16 | 1.19 | 1.22 | 1.24 | 1.27 | 1.28 | × height    |
| [Contact Phase Wrist Velocity (Normalized)](/biomechanics/activities/tennis/metrics/contact-phase-wrist-velocity-normalized) |  761 |  800 |  829 |  858 |  889 |  921 |  932 | unconfirmed |

### Landing Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                              |   5%   |  10%  |  25%  |  50%  |  75%  |  90%  |  95%  | Units    |
| ----------------------------------------------------------------------------------------------------- | :----: | :---: | :---: | :---: | :---: | :---: | :---: | -------- |
| [Finish Phase Trunk Flexion](/biomechanics/activities/tennis/metrics/finish-phase-trunk-flexion)      |   35   |   40  |   45  |   50  |   55  |   63  |   67  | deg      |
| [Finish Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/finish-phase-trunk-tilt)            |   -15  |  -12  |   -7  |   -1  |   4   |   8   |   13  | deg      |
| [Forward Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-forward)     |  0.072 | 0.151 | 0.270 | 0.361 | 0.440 | 0.509 | 0.538 | × height |
| [Open-Side Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-open-side) | -0.033 | 0.000 | 0.089 | 0.176 | 0.263 | 0.346 | 0.384 | × height |
| [Vertical Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-vertical)   |  0.095 | 0.112 | 0.129 | 0.148 | 0.168 | 0.192 | 0.202 | × height |

## Professional Sample

### Kinematic Sequence – Forward (Serve Direction) Angular Velocities & Speedups

Prefer higher velocities and speedup factors for better performance.

| Variable                                                                                                                   |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units |
| -------------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Peak Torso Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-torso-forward-angular-velocity)         |  168 |  180 |  198 |  216 |  237 |  263 |  277 | deg/s |
| [Peak Upper Arm Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-upper-arm-forward-angular-velocity) |  696 |  764 |  837 |  924 | 1031 | 1088 | 1116 | deg/s |
| [Peak Forearm Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-forearm-forward-angular-velocity)     |  637 |  772 |  921 | 1041 | 1142 | 1281 | 1325 | deg/s |
| [Forward Trunk Arm Speedup](/biomechanics/activities/tennis/metrics/forward-trunk-arm-speedup)                             | 3.29 | 3.38 | 3.74 | 4.22 | 4.81 | 5.27 | 5.42 | ratio |
| [Forward Upper Arm Forearm Speedup](/biomechanics/activities/tennis/metrics/forward-upper-arm-forearm-speedup)             | 0.57 | 0.76 | 0.98 | 1.16 | 1.31 | 1.45 | 1.54 | ratio |

### Kinematic Sequence – Twist Angular Velocities & Speedups

Prefer higher velocities and speedup factors for better performance.

| Variable                                                                                                               |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units |
| ---------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Peak Pelvis Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-pelvis-twist-angular-velocity)       |  190 |  253 |  334 |  382 |  414 |  446 |  461 | deg/s |
| [Peak Torso Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-torso-twist-angular-velocity)         |  259 |  275 |  316 |  353 |  391 |  425 |  441 | deg/s |
| [Peak Upper Arm Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-upper-arm-twist-angular-velocity) |  182 |  225 |  304 |  381 |  462 |  572 |  620 | deg/s |
| [Twist Trunk Arm Speedup](/biomechanics/activities/tennis/metrics/twist-trunk-arm-speedup)                             | 0.56 | 0.69 | 0.90 | 1.07 | 1.28 | 1.55 | 1.77 | ratio |
| [Twist Pelvis Torso Speedup](/biomechanics/activities/tennis/metrics/twist-pelvis-torso-speedup)                       | 0.70 | 0.74 | 0.84 | 0.94 | 1.07 | 1.48 | 1.75 | ratio |

### Loading Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                               |   5%   |   10%  |   25%  |   50%  |   75%  |   90%  |   95%  | Units    |
| ---------------------------------------------------------------------------------------------------------------------- | :----: | :----: | :----: | :----: | :----: | :----: | :----: | -------- |
| [Loading Phase Max Knee Flexion Front Leg](/biomechanics/activities/tennis/metrics/loading-phase-knee-flexion)         |   53   |   56   |   61   |   67   |   77   |   86   |   88   | deg      |
| [Loading Phase Max Knee Flexion Back Leg](/biomechanics/activities/tennis/metrics/loading-phase-knee-flexion)          |   56   |   62   |   71   |   78   |   85   |   89   |   93   | deg      |
| [Loading Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/loading-phase-trunk-tilt)                           |   -30  |   -28  |   -26  |   -23  |   -19  |   -14  |   -12  | deg      |
| [Loading Phase Pelvis Tilt](/biomechanics/activities/tennis/metrics/loading-phase-pelvis-tilt)                         |   -11  |   -9   |   -7   |   -5   |   -4   |   -1   |    1   | deg      |
| [Loading Phase Shoulder Hip Separation](/biomechanics/activities/tennis/metrics/loading-phase-shoulder-hip-separation) |    5   |    7   |   10   |   16   |   23   |   31   |   34   | deg      |
| [Loading Phase Ball Release Angle](/biomechanics/activities/tennis/metrics/loading-phase-ball-release-angle)           |   71   |   89   |   100  |   116  |   132  |   144  |   157  | deg      |
| [Trunk Coil](/biomechanics/activities/tennis/metrics/trunk-coil)                                                       |  -139  |  -136  |  -129  |  -122  |  -116  |  -109  |  -104  | deg      |
| [Pelvis Coil](/biomechanics/activities/tennis/metrics/pelvis-coil)                                                     |  -130  |  -129  |  -125  |  -117  |  -111  |  -101  |   -88  | deg      |
| [Trunk Stretch](/biomechanics/activities/tennis/metrics/trunk-stretch)                                                 |   128  |   135  |   146  |   155  |   162  |   170  |   173  | deg      |
| [Pelvis Stretch](/biomechanics/activities/tennis/metrics/pelvis-stretch)                                               |   94   |   103  |   113  |   125  |   135  |   142  |   146  | deg      |
| [Release Phase Elbow Angle](/biomechanics/activities/tennis/metrics/release-phase-elbow-angle)                         |    2   |    5   |   14   |   27   |   36   |   41   |   45   | deg      |
| [Max Front Knee Valgus (Normalized)](/biomechanics/activities/tennis/metrics/max-front-knee-valgus)                    | -0.039 | -0.035 | -0.028 | -0.022 | -0.014 | -0.008 | -0.006 | × height |
| [Max Back Knee Valgus (Normalized)](/biomechanics/activities/tennis/metrics/max-back-knee-valgus)                      | -0.021 | -0.019 | -0.015 | -0.011 | -0.007 | -0.005 | -0.004 | × height |

### Cocking and Acceleration Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                                                       |  5% | 10% |  25% |  50% |  75% |  90% |  95% | Units |
| ---------------------------------------------------------------------------------------------------------------------------------------------- | :-: | :-: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Cocking Phase Max Shoulder External Rotation](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-external-rotation)               | 169 | 172 |  180 |  187 |  192 |  196 |  199 | deg   |
| [Cocking Phase Shoulder Hyperangulation](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-hyperangulation)                       | 138 | 145 |  154 |  160 |  168 |  176 |  184 | deg   |
| [Cocking Phase Max X Factor](/biomechanics/activities/tennis/metrics/cocking-phase-max-x-factor)                                               |  4  |  6  |   9  |  16  |  23  |  31  |  33  | deg   |
| [Cocking Phase Shoulder Horizontal Abduction](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-horizontal-abduction)             |  84 |  88 |  93  |  98  |  104 |  109 |  111 | deg   |
| [Acceleration Phase Max Knee Extension Velocity Front Leg](/biomechanics/activities/tennis/metrics/acceleration-phase-knee-extension-velocity) | 265 | 281 |  314 |  343 |  393 |  435 |  444 | deg/s |
| [Acceleration Phase Max Knee Extension Velocity Back Leg](/biomechanics/activities/tennis/metrics/acceleration-phase-knee-extension-velocity)  | 238 | 262 |  326 |  367 |  404 |  439 |  465 | deg/s |
| [Acceleration Phase Max Elbow Extension Velocity](/biomechanics/activities/tennis/metrics/acceleration-phase-elbow-extension-velocity)         | 787 | 913 | 1058 | 1126 | 1192 | 1283 | 1338 | deg/s |

### Contact Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                                     |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units       |
| ---------------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----------- |
| [Contact Phase Elbow Flexion](/biomechanics/activities/tennis/metrics/contact-phase-elbow-flexion)                           |  24  |  27  |  31  |  37  |  44  |  49  |  54  | deg         |
| [Contact Phase Shoulder Abduction](/biomechanics/activities/tennis/metrics/contact-phase-shoulder-abduction)                 |  118 |  123 |  128 |  135 |  142 |  146 |  148 | deg         |
| [Contact Phase X Factor](/biomechanics/activities/tennis/metrics/contact-phase-x-factor)                                     |  -4  |  -2  |   2  |   5  |  10  |  15  |  19  | deg         |
| [Contact Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/contact-phase-trunk-tilt)                                 |  24  |  26  |  30  |  33  |  36  |  40  |  42  | deg         |
| [Time to Contact](/biomechanics/activities/tennis/metrics/time-to-contact)                                                   | 0.30 | 0.65 | 0.86 | 0.97 | 1.04 | 1.10 | 1.15 | s           |
| [Contact Phase Trunk Flexion](/biomechanics/activities/tennis/metrics/contact-phase-trunk-flexion)                           |  -2  |  -1  |   4  |   9  |  12  |  16  |  19  | deg         |
| [Contact Phase Trunk Rotation](/biomechanics/activities/tennis/metrics/contact-phase-trunk-rotation)                         |  -55 |  -51 |  -39 |  -32 |  -25 |  -20 |  -12 | deg         |
| [Contact Phase Pelvis Rotation](/biomechanics/activities/tennis/metrics/contact-phase-pelvis-rotation)                       |  -71 |  -59 |  -45 |  -40 |  -35 |  -30 |  -25 | deg         |
| [Contact Phase Wrist Height (Normalized)](/biomechanics/activities/tennis/metrics/contact-phase-wrist-height-normalized)     | 1.19 | 1.21 | 1.23 | 1.25 | 1.27 | 1.29 | 1.30 | × height    |
| [Contact Phase Wrist Velocity (Normalized)](/biomechanics/activities/tennis/metrics/contact-phase-wrist-velocity-normalized) |  718 |  744 |  807 |  835 |  860 |  877 |  890 | unconfirmed |

### Landing Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                              |   5%   |  10%  |  25%  |  50%  |  75%  |  90%  |  95%  | Units    |
| ----------------------------------------------------------------------------------------------------- | :----: | :---: | :---: | :---: | :---: | :---: | :---: | -------- |
| [Finish Phase Trunk Flexion](/biomechanics/activities/tennis/metrics/finish-phase-trunk-flexion)      |   27   |   32  |   39  |   46  |   52  |   58  |   61  | deg      |
| [Finish Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/finish-phase-trunk-tilt)            |   -15  |  -12  |   -7  |   -1  |   6   |   11  |   15  | deg      |
| [Forward Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-forward)     |  0.163 | 0.205 | 0.269 | 0.370 | 0.455 | 0.531 | 0.616 | × height |
| [Open-Side Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-open-side) | -0.032 | 0.001 | 0.060 | 0.167 | 0.291 | 0.371 | 0.433 | × height |
| [Vertical Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-vertical)   |  0.114 | 0.118 | 0.130 | 0.158 | 0.180 | 0.203 | 0.255 | × height |

## Broad Sample (All Levels)

### Kinematic Sequence – Forward (Serve Direction) Angular Velocities & Speedups

Prefer higher velocities and speedup factors for better performance.

| Variable                                                                                                                   |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units |
| -------------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Peak Torso Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-torso-forward-angular-velocity)         |  147 |  165 |  190 |  211 |  235 |  259 |  270 | deg/s |
| [Peak Upper Arm Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-upper-arm-forward-angular-velocity) |  651 |  723 |  825 |  905 | 1018 | 1085 | 1117 | deg/s |
| [Peak Forearm Forward Angular Velocity](/biomechanics/activities/tennis/metrics/peak-forearm-forward-angular-velocity)     |  676 |  764 |  875 | 1013 | 1130 | 1251 | 1307 | deg/s |
| [Forward Trunk Arm Speedup](/biomechanics/activities/tennis/metrics/forward-trunk-arm-speedup)                             | 3.27 | 3.38 | 3.76 | 4.29 | 4.89 | 5.42 | 5.84 | ratio |
| [Forward Upper Arm Forearm Speedup](/biomechanics/activities/tennis/metrics/forward-upper-arm-forearm-speedup)             | 0.71 | 0.80 | 0.97 | 1.13 | 1.30 | 1.45 | 1.55 | ratio |

### Kinematic Sequence – Twist Angular Velocities & Speedups

Prefer higher velocities and speedup factors for better performance.

| Variable                                                                                                               |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units |
| ---------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Peak Pelvis Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-pelvis-twist-angular-velocity)       |  190 |  224 |  305 |  376 |  422 |  462 |  494 | deg/s |
| [Peak Torso Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-torso-twist-angular-velocity)         |  256 |  279 |  324 |  364 |  401 |  435 |  461 | deg/s |
| [Peak Upper Arm Twist Angular Velocity](/biomechanics/activities/tennis/metrics/peak-upper-arm-twist-angular-velocity) |  191 |  238 |  320 |  397 |  492 |  594 |  660 | deg/s |
| [Twist Trunk Arm Speedup](/biomechanics/activities/tennis/metrics/twist-trunk-arm-speedup)                             | 0.59 | 0.70 | 0.90 | 1.09 | 1.32 | 1.66 | 1.92 | ratio |
| [Twist Pelvis Torso Speedup](/biomechanics/activities/tennis/metrics/twist-pelvis-torso-speedup)                       | 0.70 | 0.76 | 0.85 | 0.98 | 1.18 | 1.56 | 1.73 | ratio |

### Loading Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                               |   5%   |   10%  |   25%  |   50%  |   75%  |   90%  |   95%  | Units    |
| ---------------------------------------------------------------------------------------------------------------------- | :----: | :----: | :----: | :----: | :----: | :----: | :----: | -------- |
| [Loading Phase Max Knee Flexion Front Leg](/biomechanics/activities/tennis/metrics/loading-phase-knee-flexion)         |   51   |   54   |   60   |   68   |   78   |   85   |   89   | deg      |
| [Loading Phase Max Knee Flexion Back Leg](/biomechanics/activities/tennis/metrics/loading-phase-knee-flexion)          |   52   |   56   |   67   |   75   |   84   |   89   |   93   | deg      |
| [Loading Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/loading-phase-trunk-tilt)                           |   -29  |   -28  |   -25  |   -20  |   -14  |   -9   |   -5   | deg      |
| [Loading Phase Pelvis Tilt](/biomechanics/activities/tennis/metrics/loading-phase-pelvis-tilt)                         |   -11  |   -9   |   -7   |   -5   |   -2   |    0   |    2   | deg      |
| [Loading Phase Shoulder Hip Separation](/biomechanics/activities/tennis/metrics/loading-phase-shoulder-hip-separation) |    2   |    5   |   10   |   17   |   25   |   34   |   37   | deg      |
| [Loading Phase Ball Release Angle](/biomechanics/activities/tennis/metrics/loading-phase-ball-release-angle)           |   71   |   91   |   104  |   118  |   135  |   149  |   157  | deg      |
| [Trunk Coil](/biomechanics/activities/tennis/metrics/trunk-coil)                                                       |  -141  |  -138  |  -129  |  -122  |  -113  |  -106  |  -100  | deg      |
| [Pelvis Coil](/biomechanics/activities/tennis/metrics/pelvis-coil)                                                     |  -132  |  -129  |  -124  |  -116  |  -109  |   -99  |   -86  | deg      |
| [Trunk Stretch](/biomechanics/activities/tennis/metrics/trunk-stretch)                                                 |   127  |   136  |   147  |   156  |   166  |   174  |   180  | deg      |
| [Pelvis Stretch](/biomechanics/activities/tennis/metrics/pelvis-stretch)                                               |   86   |   102  |   115  |   127  |   138  |   148  |   155  | deg      |
| [Release Phase Elbow Angle](/biomechanics/activities/tennis/metrics/release-phase-elbow-angle)                         |    1   |    3   |   11   |   22   |   34   |   41   |   47   | deg      |
| [Max Front Knee Valgus (Normalized)](/biomechanics/activities/tennis/metrics/max-front-knee-valgus)                    | -0.040 | -0.035 | -0.028 | -0.021 | -0.014 | -0.008 | -0.006 | × height |
| [Max Back Knee Valgus (Normalized)](/biomechanics/activities/tennis/metrics/max-back-knee-valgus)                      | -0.022 | -0.020 | -0.015 | -0.011 | -0.007 | -0.005 | -0.004 | × height |

### Cocking and Acceleration Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                                                       |  5% | 10% |  25% |  50% |  75% |  90% |  95% | Units |
| ---------------------------------------------------------------------------------------------------------------------------------------------- | :-: | :-: | :--: | :--: | :--: | :--: | :--: | ----- |
| [Cocking Phase Max Shoulder External Rotation](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-external-rotation)               | 155 | 167 |  174 |  183 |  191 |  196 |  199 | deg   |
| [Cocking Phase Shoulder Hyperangulation](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-hyperangulation)                       | 132 | 141 |  149 |  158 |  165 |  174 |  181 | deg   |
| [Cocking Phase Max X Factor](/biomechanics/activities/tennis/metrics/cocking-phase-max-x-factor)                                               |  0  |  3  |   9  |  17  |  24  |  33  |  36  | deg   |
| [Cocking Phase Shoulder Horizontal Abduction](/biomechanics/activities/tennis/metrics/cocking-phase-shoulder-horizontal-abduction)             |  60 |  72 |  86  |  95  |  101 |  107 |  110 | deg   |
| [Acceleration Phase Max Knee Extension Velocity Front Leg](/biomechanics/activities/tennis/metrics/acceleration-phase-knee-extension-velocity) | 251 | 272 |  307 |  345 |  389 |  428 |  440 | deg/s |
| [Acceleration Phase Max Knee Extension Velocity Back Leg](/biomechanics/activities/tennis/metrics/acceleration-phase-knee-extension-velocity)  | 211 | 250 |  312 |  359 |  396 |  430 |  448 | deg/s |
| [Acceleration Phase Max Elbow Extension Velocity](/biomechanics/activities/tennis/metrics/acceleration-phase-elbow-extension-velocity)         | 787 | 902 | 1049 | 1136 | 1220 | 1312 | 1352 | deg/s |

### Contact Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                                                     |  5%  |  10% |  25% |  50% |  75% |  90% |  95% | Units       |
| ---------------------------------------------------------------------------------------------------------------------------- | :--: | :--: | :--: | :--: | :--: | :--: | :--: | ----------- |
| [Contact Phase Elbow Flexion](/biomechanics/activities/tennis/metrics/contact-phase-elbow-flexion)                           |  25  |  28  |  34  |  41  |  49  |  57  |  63  | deg         |
| [Contact Phase Shoulder Abduction](/biomechanics/activities/tennis/metrics/contact-phase-shoulder-abduction)                 |  106 |  112 |  122 |  129 |  138 |  144 |  147 | deg         |
| [Contact Phase X Factor](/biomechanics/activities/tennis/metrics/contact-phase-x-factor)                                     |  -5  |  -3  |   1  |   5  |  10  |  15  |  18  | deg         |
| [Contact Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/contact-phase-trunk-tilt)                                 |  23  |  27  |  31  |  35  |  39  |  43  |  46  | deg         |
| [Time to Contact](/biomechanics/activities/tennis/metrics/time-to-contact)                                                   | 0.31 | 0.67 | 0.82 | 0.94 | 1.03 | 1.12 | 1.18 | s           |
| [Contact Phase Trunk Flexion](/biomechanics/activities/tennis/metrics/contact-phase-trunk-flexion)                           |  -2  |   1  |   6  |  10  |  15  |  21  |  28  | deg         |
| [Contact Phase Trunk Rotation](/biomechanics/activities/tennis/metrics/contact-phase-trunk-rotation)                         |  -53 |  -45 |  -37 |  -30 |  -21 |  -10 |  -5  | deg         |
| [Contact Phase Pelvis Rotation](/biomechanics/activities/tennis/metrics/contact-phase-pelvis-rotation)                       |  -66 |  -51 |  -42 |  -37 |  -31 |  -23 |  -19 | deg         |
| [Contact Phase Wrist Height (Normalized)](/biomechanics/activities/tennis/metrics/contact-phase-wrist-height-normalized)     | 1.15 | 1.18 | 1.21 | 1.24 | 1.26 | 1.28 | 1.29 | × height    |
| [Contact Phase Wrist Velocity (Normalized)](/biomechanics/activities/tennis/metrics/contact-phase-wrist-velocity-normalized) |  704 |  745 |  813 |  843 |  869 |  899 |  917 | unconfirmed |

### Landing Phase

Deviations from center indicate atypical positioning, not necessarily poor performance.

| Variable                                                                                              |   5%   |  10%  |  25%  |  50%  |  75%  |  90%  |  95%  | Units    |
| ----------------------------------------------------------------------------------------------------- | :----: | :---: | :---: | :---: | :---: | :---: | :---: | -------- |
| [Finish Phase Trunk Flexion](/biomechanics/activities/tennis/metrics/finish-phase-trunk-flexion)      |   29   |   35  |   42  |   48  |   55  |   61  |   65  | deg      |
| [Finish Phase Trunk Tilt](/biomechanics/activities/tennis/metrics/finish-phase-trunk-tilt)            |   -16  |  -12  |   -7  |   -1  |   5   |   11  |   14  | deg      |
| [Forward Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-forward)     |  0.065 | 0.160 | 0.261 | 0.362 | 0.446 | 0.519 | 0.574 | × height |
| [Open-Side Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-open-side) | -0.037 | 0.000 | 0.073 | 0.169 | 0.277 | 0.354 | 0.411 | × height |
| [Vertical Displacement (Normalized)](/biomechanics/activities/tennis/metrics/displacement-vertical)   |  0.108 | 0.117 | 0.130 | 0.154 | 0.179 | 0.200 | 0.237 | × height |
