ORIGINAL ARTICLES   

The Journal of Sports Medicine and Physical Fitness 2000 September;40(3):223-32

Copyright © 2001 EDIZIONI MINERVA MEDICA

language: English

Intra-abdominal pressure and rowing: the effects of inspiring versus expiring during the drive

Manning T. S., Plowman S. A., Drake G., Looney M. A., Ball T. E.

Department of Kinesiology and Physical Education, Northern Illinois University, DeKalb, IL, USA

Background. The lum­bar ver­te­brae of row­ers are sub­jected to ­high lev­els of ­shear and com­pres­sion at mid-­drive, but ­intra-abdom­i­nal pres­sure (IAP) may par­tial­ly neu­tral­ize ­these forc­es. IAP fluc­tu­ates ­with breath­ing. ­This ­study com­pared the IAP ­between inspir­ing dur­ing the ­drive and expir­ing dur­ing the ­drive.
Methods. Experimental ­design: ­ten vol­un­teers per­formed one 5×2-min­ute rep­e­ti­tion ­test ­while ispir­ing dur­ing the ­drive and one 5×2-min­ute rep­e­ti­tion ­test ­while expir­ing dur­ing the ­drive on a row­ing ergom­e­ter. The ­five ­work ­rates ­were: 100, 125, 150, 175 and 200 ­watts at 22, 24, 26, 28 and 30 ­strokes per min­ute, respec­tive­ly. Measures: the move­ment of the ­body ­while row­ing was ana­lyzed ­using a posi­tion sen­sor, and IAP was meas­ured ­using a pres­sure trans­duc­er cath­e­ter.
Results. A 2×5 repeat­ed meas­ures anal­y­sis of var­i­ance ­showed ­that ­there was a sig­nif­i­cant inter­ac­tion for the depen­dent vari­a­ble mid-­drive IAP (p<0.05), ­with the mid-­drive IAP increas­ing at a great­er ­rate ­while expir­ing dur­ing the ­drive rel­a­tive to inspir­ing dur­ing the ­drive. Across ­work ­rate, the ­mid-­drive IAP and min­i­mal IAP ­were sig­nif­i­cant­ly high­er ­while expir­ing dur­ing the ­drive ­than inspir­ing dur­ing the ­drive (p<0.05). ­Across breath­ing pat­tern, the min­i­mal IAP, max­i­mal IAP, aver­age ­change in IAP and mid-­drive IAP ­increased sig­nif­i­cant­ly ­with ­work ­rate (p<0.05).
Conclusions. The ­data ­show ­that expir­ing dur­ing the ­drive ­leads to a great­er mid-­drive IAP ­than inspir­ing dur­ing the ­drive.