(STACKER) – While many Americans spend most of their working days glued to a computer screen, others exert a great deal of energy due to the physical nature of their work.

Stacker ranked the 50 most physically demanding jobs in America using data from the Occupational Information Network, or O*NET, a system developed by the U.S. Department of Labor providing information for 873 occupations within the United States economy. O*NET uses professional occupational analysts to determine the importance of certain skills and abilities, as well as the appropriate level of accomplishment needed, to perform specific jobs. The analysis also includes average earnings, employment, and projected job growth.

The jobs on this list are ranked by the importance of having stamina, or the necessary capacity for long-term exertion, which factors in the work of different muscle groups in different jobs, on a scale from 0 to 100. Ties were broken by both the level of stamina required, also on a scale from 0 to 100, and the average wage in 2021. Some wages are reported as either hourly or salary rather than both due to differences in pay structures for some occupations.

Stacker also examined detailed responsibilities and work activities included for each job to see what kind of physical activities are required, such as climbing, lifting, walking, stooping, handling sizable machinery, or working in hazardous or outdoor conditions.

50. Brickmasons and blockmasons

49. Lifeguards, ski patrol, and other recreational protective service workers

48. Helpers—installation, maintenance, and repair workers

47. Helpers—brickmasons, blockmasons, stonemasons, and tile and marble setters

46. Tire builders

45. Wind turbine service technicians

44. Rail car repairers

43. Transit and railroad police

42. First-line supervisors of correctional officers

41. Correctional officers and jailers

40. Helpers—roofers

39. Extruding, forming, pressing, and compacting machine setters, operators, and tenders

38. Adhesive bonding machine operators and tenders

37. Foundry mold and coremakers

36. Dining room and cafeteria attendants and bartender helpers

35. Tank car, truck, and ship loaders

34. Automotive and watercraft service attendants

33. Sawing machine setters, operators, and tenders, wood

32. Helpers—extraction workers

31. Carpet installers

30. Plasterers and stucco masons

29. Forest and conservation workers

28. Laborers and freight, stock, and material movers, hand

27. Fence erectors

26. Construction laborers

25. Highway maintenance workers

24. Massage therapists

23. Drywall and ceiling tile installers

22. Terrazzo workers and finishers

21. Roof bolters, mining

20. Electrical power-line installers and repairers

19. Commercial divers

18. Rock splitters, quarry

17. Cement masons and concrete finishers

16. Heat treating equipment setters, operators, and tenders, metal and plastic

15. Floor sanders and finishers

14. Tree trimmers and pruners

13. Roofers

12. Reinforcing iron and rebar workers

11. Fallers

10. Farmworkers and laborers, crop, nursery, and greenhouse

9. Stonemasons

8. Structural iron and steel workers

7. Manufactured building and mobile home installers

6. Derrick operators, oil and gas

5. Firefighters

4. Choreographers

3. Exercise trainers and group fitness instructors

2. Athletes and sports competitors

1. Dancers