XXXX consumption of elite distance runners on an anti-gravity treadmill  .

@entity1 @entity26 @entity1053 @entity4962
Lower body positive pressure (LBPP), or 'anti-gravity' treadmills   have become increasingly popular among elite distance runners. However, to date, few studies have assessed the effect of body weight support ( @entity1053 ) on the metabolic cost of running among elite runners. This study evaluated how @entity1053 influenced the relationship between velocity and metabolic cost among 6 elite male distance runners. @entity1 ran three- 16 minute tests consisting of 4 stages of 4 minutes at 8, 7, 6 and 5 min  mile(-1) pace (3.35, 3.84, 4.47 and 5.36 m  s(-1)), while maintaining an aerobic effort (Respiratory Exchange Ratio  <=1.00). One test was run on a regular treadmill, one on an anti-gravity treadmill with 40% @entity1053 and one with 20% @entity1053 being provided. Expired gas data were collected and regression equations used to determine and compare slopes. Significant decreases in @entity26 uptake ( @entity4962 ) were found with each increase in @entity1053 (p < 0.001). At 20% @entity1053 , the average decrease in net VO2 was greater than proportional (34%), while at 40% @entity1053 , the average net reduction in VO2 was close to proportional (38%). Across velocities, the slope of the relationship between VO2 and velocity (  @entity4962 /  v) was steeper with less support. The slopes at both the 20% and 40% @entity1053 conditions were similar, especially when compared to the regular treadmill. Variability in VO2 between athletes was much greater on the LBPP treadmill and was greater with increased levels of @entity1053 . In this study we evaluated the effect of body weight support on @entity4962 among elite distance runners. We have shown that @entity26 uptake decreased with support, but not in direct proportion to that support. Further, because of the high variability in @entity26 uptake between athletes on the LBPP treadmill, prediction equations may not be reliable and other indicators (heart rate, perceived exertion or directly measured @entity26 uptake) should be used to guide training intensity when training on the LBPP treadmill. Key pointsWith increasing amounts of @entity1053 ( @entity1053 ), the slope of the relationship between velocity and @entity26 consumption (  @entity4962 /  v) decreases significantly. This means the change in @entity26 consumption (VO2) is significantly smaller over a given change in velocity at higher amounts of @entity1053 .There is a non-linear decrease in VO2 with increasing @entity1053 . As such, with each increment in the amount of @entity1053 provided, the reduction in VO2 becomes increasingly smaller.This paper provides first of its kind data on the effects of @entity1053 on the cost of running among highly trained, elite runners. The outcomes of this study are in line with previous findings among non-elite runners.
