Effects of milking unit design on upper extremity muscle activity during attachment among U.S. large-herd parlor workers

Details

• Alternative Title:
  Appl Ergon
• Personal Author:
  Douphrate, David I ; Gimeno, David ; Nonnenmann, Matthew W ; Hagevoort, Robert ; Reynolds, Stephen J ; Rodriguez, Anabel ; Fethke, Nathan B
• Description:
  Background
  
  Large-herd dairy parlor workers experience a high prevalence of musculoskeletal symptoms in the upper extremity. The purpose of this study was to evaluate the effect of milking unit design on upper extremity muscle activity during milking unit attachment.
  
  Methods
  
  Upper extremity muscle activity was recorded among U.S. large-herd parlor workers (n=11) using surface electromyography. Participants performed several milking unit attachment cycles with each of six milking unit designs. Muscle activity levels were then compared between unit designs.
  
  Results
  
  Mean muscle activity levels (in %MVE) across milking units ranged from 6.8 to 8.2 for the upper trapezius, 8.2 to 10.3 for the anterior deltoid, 13.8 to 17.2 for the forearm flexors, and 9.9 to 12.4 for the forearm extensors. Pairwise comparisons between milking units did not reveal statistically significant differences in muscle activity levels across milking unit designs. However, a general pattern of higher muscle activity was observed with specific milking units. Milking unit weight, milk tube spread, and teat cup shape may explain differences in muscle activity levels.
  
  Conclusions
  
  Milking unit design may influence muscle activity levels among parlor workers. Small reductions in muscle activity associated with milking unit design have the potential to delay the onset of fatigue or development of musculoskeletal health outcomes among parlor workers.
  
  
• Subjects:
  Adult Article Biomechanical Phenomena Dairy Dairying Deltoid Muscle Electromyography Equipment Equipment Design Ergonomics Forearm Humans Male Milking Unit Superficial Back Muscles Task Performance And Analysis United States Young Adult

  More +
• Source:
  Appl Ergon. 58:482-490
• Pubmed ID:
  27633245
• Pubmed Central ID:
  PMC7008452
• Document Type:
  Journal Article
• Funding:
  U54 OH008085/OH/NIOSH CDC HHS/United States
• Volume:
  58
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:4502308c37fd9713ae10813ff4b16390fad80823b53addc814f338fb55129e6c
• Download URL:
  https://stacks.cdc.gov/view/cdc/85012/cdc_85012_DS1.pdf
• File Type:
  [PDF - 773.67 KB ]