This study evaluates the effects of intestinal failure (IF) on muscle strength, speed, agility, and body composition (BC), and it identifies clinical markers that may predict impairment as the number of children with IF receiving long-term parenteral nourishment (PN) continues to rise. IF on PN: a cross-sectional study of children aged 5-18. Grip strength and the strength and agility subtest of the Bruininks-Oseretsky Test of Motor Proficiency (BOT-2) were also used as performance measures. Chart abstraction was used to collect data on BC based on dual-energy x-ray absorptiometry DXA readings and other clinical factors. Comparisons were made to population norms and controls of the same age and gender. Among the participants were 21 kids with IF (14 boys) and 33  kids without IF (20  boys), with a median age of 8.33 (IQR: 6.96-11.04) and a range of 6.67-10.79. Grip strength (P=0.001) and speed (P<0.001) were also different between the groups. Of the 21 children with IF, 9 had BOT-2 scores more than 1 SD below the mean, and 13 had grip strength more than 1 SD below the mean. Around 10 out of 18 children (56%) had a lower percentage of fat-free mass (FFM), and a higher percentage of fat mass (FM) compared to the reference norms, as measured by DXA. There was a correlation between FFM% and BOT-2 scores (r = 0.479, P=0.044) and between FFM% and grip strength scores (P=0.047, 1 SD below the mean). Other clinical factors, including prematurity, height, hospitalizations, sepsis, and small bowel length, also impacted strength and agility. Children with IF may experience changes in BC and a reduction in muscle strength and agility. Improving health outcomes requires constant medical, dietary, and rehabilitation attention.