Leg Press vs Machine Back Extension Strength Standards
Compare your leg press and machine back extension against strength standards for your sex and bodyweight. Enter one recent set of 1–12 reps for each lift to see your estimated one-rep maxes, strength levels, next targets, and which lift you should prioritize.
Use each exercise's canonical input: Total plates loaded on the 45-degree sled for Leg Press and Displayed machine or cable resistance for Machine Back Extension. Use a bilateral 45-degree plate-loaded sled leg press with flat shoulder-width feet, thighs reaching at least parallel to the platform, stable hips and lower back, and full controlled knee extension and Use the tested Machine Back Extension machine only. You can enter either lift in pounds or kilograms. Each lift is compared with its own standards, so the heavier lift is not automatically the stronger one.
Leg Press vs Machine Back Extension Strength Standards by Bodyweight
Use these tables to compare the estimated one-rep max required for the 45-degree leg press and machine back extension to reach the same strength level at each listed bodyweight. They show the targets used by the calculator—not a required difference between your 45-degree leg press and machine back extension.
Choose the men’s or women’s table, find your bodyweight or the closest listed row, then read across to Novice, Intermediate, Advanced, or Elite. Every entry shows Leg Press / Machine Back Extension, with pounds first and kilograms underneath. For a result based on your exact bodyweight and recent sets, use the calculator above; you do not need to test either true one-rep max.
Men’s Leg Press vs Machine Back Extension Standards
How to read the table: The first number is Leg Press; the second is Machine Back Extension. Each number is the lowest estimated one-rep max needed to reach that strength level. Scroll horizontally on smaller screens.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 120 lb 54.4 kg | 168 / 42 lb 76.2 / 19.1 kg | 252 / 67 lb 114.3 / 30.4 kg | 350 / 101 lb 158.8 / 45.8 kg | 448 / 134 lb 203.2 / 60.8 kg |
| 130 lb 59 kg | 177 / 44 lb 80.3 / 20 kg | 266 / 71 lb 120.7 / 32.2 kg | 369 / 106 lb 167.4 / 48.1 kg | 472 / 141 lb 214.1 / 64 kg |
| 140 lb 63.5 kg | 186 / 47 lb 84.4 / 21.3 kg | 279 / 74 lb 126.6 / 33.6 kg | 388 / 112 lb 176 / 50.8 kg | 496 / 148 lb 225 / 67.1 kg |
| 150 lb 68 kg | 195 / 49 lb 88.5 / 22.2 kg | 292 / 78 lb 132.4 / 35.4 kg | 406 / 117 lb 184.2 / 53.1 kg | 519 / 155 lb 235.4 / 70.3 kg |
| 160 lb 72.6 kg | 203 / 51 lb 92.1 / 23.1 kg | 305 / 81 lb 138.3 / 36.7 kg | 424 / 122 lb 192.3 / 55.3 kg | 542 / 162 lb 245.8 / 73.5 kg |
| 170 lb 77.1 kg | 212 / 53 lb 96.2 / 24 kg | 318 / 84 lb 144.2 / 38.1 kg | 441 / 127 lb 200 / 57.6 kg | 565 / 169 lb 256.3 / 76.7 kg |
| 180 lb 81.6 kg | 220 / 55 lb 99.8 / 24.9 kg | 330 / 88 lb 149.7 / 39.9 kg | 458 / 132 lb 207.7 / 59.9 kg | 586 / 176 lb 265.8 / 79.8 kg |
| 190 lb 86.2 kg | 228 / 57 lb 103.4 / 25.9 kg | 342 / 91 lb 155.1 / 41.3 kg | 475 / 137 lb 215.5 / 62.1 kg | 608 / 182 lb 275.8 / 82.6 kg |
| 200 lb 90.7 kg | 236 / 59 lb 107 / 26.8 kg | 354 / 94 lb 160.6 / 42.6 kg | 492 / 142 lb 223.2 / 64.4 kg | 629 / 188 lb 285.3 / 85.3 kg |
| 210 lb 95.3 kg | 244 / 61 lb 110.7 / 27.7 kg | 366 / 97 lb 166 / 44 kg | 508 / 146 lb 230.4 / 66.2 kg | 650 / 195 lb 294.8 / 88.5 kg |
| 220 lb 99.8 kg | 251 / 63 lb 113.9 / 28.6 kg | 377 / 100 lb 171 / 45.4 kg | 524 / 151 lb 237.7 / 68.5 kg | 670 / 201 lb 303.9 / 91.2 kg |
| 230 lb 104.3 kg | 259 / 65 lb 117.5 / 29.5 kg | 388 / 103 lb 176 / 46.7 kg | 540 / 156 lb 244.9 / 70.8 kg | 691 / 207 lb 313.4 / 93.9 kg |
| 240 lb 108.9 kg | 266 / 67 lb 120.7 / 30.4 kg | 400 / 106 lb 181.4 / 48.1 kg | 555 / 160 lb 251.7 / 72.6 kg | 710 / 213 lb 322.1 / 96.6 kg |
| 250 lb 113.4 kg | 274 / 68 lb 124.3 / 30.8 kg | 411 / 109 lb 186.4 / 49.4 kg | 570 / 165 lb 258.5 / 74.8 kg | 730 / 219 lb 331.1 / 99.3 kg |
| 260 lb 117.9 kg | 281 / 70 lb 127.5 / 31.8 kg | 422 / 112 lb 191.4 / 50.8 kg | 585 / 169 lb 265.4 / 76.7 kg | 749 / 224 lb 339.7 / 101.6 kg |
| 270 lb 122.5 kg | 288 / 72 lb 130.6 / 32.7 kg | 432 / 115 lb 196 / 52.2 kg | 600 / 173 lb 272.2 / 78.5 kg | 768 / 230 lb 348.4 / 104.3 kg |
| 280 lb 127 kg | 295 / 74 lb 133.8 / 33.6 kg | 443 / 118 lb 200.9 / 53.5 kg | 615 / 177 lb 279 / 80.3 kg | 787 / 236 lb 357 / 107 kg |
| 290 lb 131.5 kg | 302 / 76 lb 137 / 34.5 kg | 453 / 121 lb 205.5 / 54.9 kg | 630 / 182 lb 285.8 / 82.6 kg | 806 / 241 lb 365.6 / 109.3 kg |
| 300 lb 136.1 kg | 309 / 77 lb 140.2 / 34.9 kg | 464 / 123 lb 210.5 / 55.8 kg | 644 / 186 lb 292.1 / 84.4 kg | 824 / 247 lb 373.8 / 112 kg |
Women’s Leg Press vs Machine Back Extension Standards
How to read the table: The first number is Leg Press; the second is Machine Back Extension. Each number is the lowest estimated one-rep max needed to reach that strength level. Scroll horizontally on smaller screens.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 100 lb 45.4 kg | 114 / 25 lb 51.7 / 11.3 kg | 172 / 41 lb 78 / 18.6 kg | 240 / 63 lb 108.9 / 28.6 kg | 309 / 86 lb 140.2 / 39 kg |
| 110 lb 49.9 kg | 122 / 27 lb 55.3 / 12.2 kg | 183 / 44 lb 83 / 20 kg | 256 / 67 lb 116.1 / 30.4 kg | 329 / 92 lb 149.2 / 41.7 kg |
| 120 lb 54.4 kg | 129 / 28 lb 58.5 / 12.7 kg | 194 / 47 lb 88 / 21.3 kg | 271 / 72 lb 122.9 / 32.7 kg | 349 / 97 lb 158.3 / 44 kg |
| 130 lb 59 kg | 136 / 30 lb 61.7 / 13.6 kg | 205 / 49 lb 93 / 22.2 kg | 286 / 75 lb 129.7 / 34 kg | 368 / 103 lb 166.9 / 46.7 kg |
| 140 lb 63.5 kg | 143 / 32 lb 64.9 / 14.5 kg | 215 / 52 lb 97.5 / 23.6 kg | 301 / 79 lb 136.5 / 35.8 kg | 387 / 108 lb 175.5 / 49 kg |
| 150 lb 68 kg | 150 / 33 lb 68 / 15 kg | 225 / 54 lb 102.1 / 24.5 kg | 315 / 83 lb 142.9 / 37.6 kg | 405 / 113 lb 183.7 / 51.3 kg |
| 160 lb 72.6 kg | 157 / 34 lb 71.2 / 15.4 kg | 235 / 56 lb 106.6 / 25.4 kg | 329 / 87 lb 149.2 / 39.5 kg | 423 / 118 lb 191.9 / 53.5 kg |
| 170 lb 77.1 kg | 163 / 36 lb 73.9 / 16.3 kg | 245 / 59 lb 111.1 / 26.8 kg | 342 / 90 lb 155.1 / 40.8 kg | 440 / 123 lb 199.6 / 55.8 kg |
| 180 lb 81.6 kg | 169 / 37 lb 76.7 / 16.8 kg | 254 / 61 lb 115.2 / 27.7 kg | 356 / 94 lb 161.5 / 42.6 kg | 457 / 128 lb 207.3 / 58.1 kg |
| 190 lb 86.2 kg | 176 / 39 lb 79.8 / 17.7 kg | 263 / 63 lb 119.3 / 28.6 kg | 369 / 97 lb 167.4 / 44 kg | 474 / 132 lb 215 / 59.9 kg |
| 200 lb 90.7 kg | 182 / 40 lb 82.6 / 18.1 kg | 273 / 65 lb 123.8 / 29.5 kg | 382 / 101 lb 173.3 / 45.8 kg | 491 / 137 lb 222.7 / 62.1 kg |
| 210 lb 95.3 kg | 188 / 41 lb 85.3 / 18.6 kg | 282 / 68 lb 127.9 / 30.8 kg | 394 / 104 lb 178.7 / 47.2 kg | 507 / 141 lb 230 / 64 kg |
| 220 lb 99.8 kg | 194 / 43 lb 88 / 19.5 kg | 290 / 70 lb 131.5 / 31.8 kg | 407 / 107 lb 184.6 / 48.5 kg | 523 / 146 lb 237.2 / 66.2 kg |
| 230 lb 104.3 kg | 199 / 44 lb 90.3 / 20 kg | 299 / 72 lb 135.6 / 32.7 kg | 419 / 110 lb 190.1 / 49.9 kg | 539 / 150 lb 244.5 / 68 kg |
| 240 lb 108.9 kg | 205 / 45 lb 93 / 20.4 kg | 308 / 74 lb 139.7 / 33.6 kg | 431 / 114 lb 195.5 / 51.7 kg | 554 / 155 lb 251.3 / 70.3 kg |
How Your Leg Press vs Machine Back Extension Result Is Calculated
The calculator estimates each max, rates it against the standards for that exercise and bodyweight, then compares the two ratings. Here is the complete process.
1. Estimate a one-rep max from each set
For one rep, it uses the weight entered. For 2–12 reps, it runs both formulas and keeps the lower, less aggressive estimate.
- Epley: weight × (1 + reps ÷ 30)
- Brzycki: weight × 36 ÷ (37 − reps)
A published back-squat study supports estimated-max prediction under its study conditions. It does not independently validate every exercise or population used by this comparison. Estimates are more dependable from clean, difficult, lower-rep sets. See the Back-squat formula validation study and Published discussion of back-squat one-rep-max prediction research.
2. Find the 45-degree leg press strength level
The leg press standards use the sex-specific standards from the individual Leg Press tool. Targets begin at 190 lb for men and 150 lb for women, then adjust to your exact bodyweight: reference target × (user bodyweight ÷ reference bodyweight) to the two-thirds power.
The target rises more slowly than bodyweight so heavier lifters are expected to press more sled load without requiring strength to increase pound for pound.
3. Find the machine back extension strength level
The standards use the sex-specific thresholds from the individual Machine Back Extension tool. Targets begin at 190 lb for men and 150 lb for women, then adjust to your exact bodyweight: reference target × (user bodyweight ÷ reference bodyweight) to the two-thirds power.
The target rises more slowly than bodyweight so larger lifters are expected to lift more without requiring strength to increase pound for pound.
4. Compare the two results
Each max receives a level from Beginner through Elite. The lower-level lift is the priority. If the levels match, a priority appears only when one lift is at least 10 points farther from its next level. Otherwise, the result is Balanced.
The result shows which lift ranks lower, not why. Technique, fatigue, training history, and set quality can affect it. Age range is recorded anonymously but does not change the standards.
| Stage | What happens |
|---|---|
| Estimate each max | Use the entered weight for 1 rep; for 2–12 reps, keep the lower formula result. |
| Rate the leg press | Adjust 45-degree leg press targets to exact bodyweight with the two-thirds rule. |
| Rate the machine back extension | Use the canonical estimated max and adjust targets to exact bodyweight with the approved two-thirds rule. |
| Compare different levels | Name the lower-level lift as the priority. |
| Compare matching levels | Use Balanced unless the difference in progress toward the next level reaches 10 points. |
Use the calculator above to see both estimated maxes, strength levels, the priority or Balanced result, and both next-level targets.
How Men’s Leg Press and Machine Back Extension Standards Differ
How to read both charts: Choose a strength level, find bodyweight along the bottom, and follow that level’s line. Zero means the two standards are equal. Above zero means the machine back extension standard is higher; below zero means the 45-degree leg press standard is higher. On a phone, swipe the chart left and right to inspect the full-size lines and labels. The tables provide the exact pounds and kilograms.
What the men’s data shows:
The standards come closest at 120 lb.
Novice, Intermediate, Advanced, and Elite at every displayed bodyweight.
142.4 → 261.8 kg from 120 to 300 lb bodyweight.
How to read the table: Every number is the machine back extension standard minus the 45-degree leg press standard. A plus sign means the machine back extension standard is higher. A minus sign means the 45-degree leg press standard is higher.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 120 lb 54.4 kg | −126 lb −57.1 kg | −185 lb −83.9 kg | −249 lb −113 kg | −314 lb −142.4 kg |
| 130 lb 59 kg | −133 lb −60.3 kg | −195 lb −88.5 kg | −263 lb −119.3 kg | −331 lb −150.1 kg |
| 140 lb 63.5 kg | −139 lb −63.1 kg | −205 lb −93 kg | −276 lb −125.2 kg | −348 lb −157.9 kg |
| 150 lb 68 kg | −146 lb −66.3 kg | −214 lb −97 kg | −289 lb −131.1 kg | −364 lb −165.1 kg |
| 160 lb 72.6 kg | −152 lb −69 kg | −224 lb −101.6 kg | −302 lb −137 kg | −380 lb −172.3 kg |
| 170 lb 77.1 kg | −159 lb −72.2 kg | −234 lb −106.1 kg | −314 lb −142.4 kg | −396 lb −179.6 kg |
| 180 lb 81.6 kg | −165 lb −74.9 kg | −242 lb −109.8 kg | −326 lb −147.8 kg | −410 lb −186 kg |
| 190 lb 86.2 kg | −171 lb −77.5 kg | −251 lb −113.8 kg | −338 lb −153.4 kg | −426 lb −193.2 kg |
| 200 lb 90.7 kg | −177 lb −80.2 kg | −260 lb −118 kg | −350 lb −158.8 kg | −441 lb −200 kg |
| 210 lb 95.3 kg | −183 lb −83 kg | −269 lb −122 kg | −362 lb −164.2 kg | −455 lb −206.3 kg |
| 220 lb 99.8 kg | −188 lb −85.3 kg | −277 lb −125.6 kg | −373 lb −169.2 kg | −469 lb −212.7 kg |
| 230 lb 104.3 kg | −194 lb −88 kg | −285 lb −129.3 kg | −384 lb −174.1 kg | −484 lb −219.5 kg |
| 240 lb 108.9 kg | −199 lb −90.3 kg | −294 lb −133.3 kg | −395 lb −179.1 kg | −497 lb −225.5 kg |
| 250 lb 113.4 kg | −206 lb −93.5 kg | −302 lb −137 kg | −405 lb −183.7 kg | −511 lb −231.8 kg |
| 260 lb 117.9 kg | −211 lb −95.7 kg | −310 lb −140.6 kg | −416 lb −188.7 kg | −525 lb −238.1 kg |
| 270 lb 122.5 kg | −216 lb −97.9 kg | −317 lb −143.8 kg | −427 lb −193.7 kg | −538 lb −244.1 kg |
| 280 lb 127 kg | −221 lb −100.2 kg | −325 lb −147.4 kg | −438 lb −198.7 kg | −551 lb −250 kg |
| 290 lb 131.5 kg | −226 lb −102.5 kg | −332 lb −150.6 kg | −448 lb −203.2 kg | −565 lb −256.3 kg |
| 300 lb 136.1 kg | −232 lb −105.3 kg | −341 lb −154.7 kg | −458 lb −207.7 kg | −577 lb −261.8 kg |
How Women’s Leg Press and Machine Back Extension Standards Differ
What the women’s data shows:
The standards come closest at 100 lb.
Novice, Intermediate, Advanced, and Elite at every displayed bodyweight.
101.2 → 181 kg from 100 to 240 lb bodyweight.
How to read the table: Every number is the machine back extension standard minus the 45-degree leg press standard. A plus sign means the machine back extension standard is higher. A minus sign means the 45-degree leg press standard is higher.
| Bodyweight | Novice | Intermediate | Advanced | Elite |
|---|---|---|---|---|
| 100 lb 45.4 kg | −89 lb −40.4 kg | −131 lb −59.4 kg | −177 lb −80.3 kg | −223 lb −101.2 kg |
| 110 lb 49.9 kg | −95 lb −43.1 kg | −139 lb −63 kg | −189 lb −85.7 kg | −237 lb −107.5 kg |
| 120 lb 54.4 kg | −101 lb −45.8 kg | −147 lb −66.7 kg | −199 lb −90.2 kg | −252 lb −114.3 kg |
| 130 lb 59 kg | −106 lb −48.1 kg | −156 lb −70.8 kg | −211 lb −95.7 kg | −265 lb −120.2 kg |
| 140 lb 63.5 kg | −111 lb −50.4 kg | −163 lb −73.9 kg | −222 lb −100.7 kg | −279 lb −126.5 kg |
| 150 lb 68 kg | −117 lb −53 kg | −171 lb −77.6 kg | −232 lb −105.3 kg | −292 lb −132.4 kg |
| 160 lb 72.6 kg | −123 lb −55.8 kg | −179 lb −81.2 kg | −242 lb −109.7 kg | −305 lb −138.4 kg |
| 170 lb 77.1 kg | −127 lb −57.6 kg | −186 lb −84.3 kg | −252 lb −114.3 kg | −317 lb −143.8 kg |
| 180 lb 81.6 kg | −132 lb −59.9 kg | −193 lb −87.5 kg | −262 lb −118.9 kg | −329 lb −149.2 kg |
| 190 lb 86.2 kg | −137 lb −62.1 kg | −200 lb −90.7 kg | −272 lb −123.4 kg | −342 lb −155.1 kg |
| 200 lb 90.7 kg | −142 lb −64.5 kg | −208 lb −94.3 kg | −281 lb −127.5 kg | −354 lb −160.6 kg |
| 210 lb 95.3 kg | −147 lb −66.7 kg | −214 lb −97.1 kg | −290 lb −131.5 kg | −366 lb −166 kg |
| 220 lb 99.8 kg | −151 lb −68.5 kg | −220 lb −99.7 kg | −300 lb −136.1 kg | −377 lb −171 kg |
| 230 lb 104.3 kg | −155 lb −70.3 kg | −227 lb −102.9 kg | −309 lb −140.2 kg | −389 lb −176.5 kg |
| 240 lb 108.9 kg | −160 lb −72.6 kg | −234 lb −106.1 kg | −317 lb −143.8 kg | −399 lb −181 kg |
Leg Press and Machine Back Extension Exercises Used by This Calculator
This calculator uses a bilateral 45-degree sled leg press and a strict machine back extension test. Use strict canonical Leg Press and Machine Back Extension tests. Do not mix variations, assistance, partial range, momentum, or different load conventions.
Use a 45-degree plate-loaded sled leg press
Keep both feet flat and approximately shoulder-width, descend until the thighs reach at least parallel to the platform without lifting the hips or rounding the lower back, and press to controlled full knee extension. Do not enter a horizontal, vertical, selectorized, single-leg, high-foot, partial, bounced, or assisted press.
Use the canonical Machine Back Extension setup and load convention
Use the tested Machine Back Extension machine only Enter external resistance for the set Use matching units for bodyweight and resistance Keep setup and range consistent Count only strict controlled reps Do not enter a different exercise result
Enter one recent Leg Press result and one recent Machine Back Extension result
Use each exercise’s canonical input: Total plates loaded on the 45-degree sled for Leg Press and Displayed machine or cable resistance for Machine Back Extension.
Related Tools
- Leg Press (45° Sled) — View the individual Leg Press standards and next strength-level target.
- Machine Back Extension — View the individual Machine Back Extension standards and next strength-level target.
- Cable Pull Through — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.
- Romanian Deadlift — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.
- Barbell Good Morning — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.
- Barbell Deadlift — Use this related standards tool to compare a registry-approved neighboring exercise without mixing its result into this comparison.