title: The 1-Minute Sit-to-Stand Test in Adults With Cystic Fibrosis: Correlations With Cardiopulmonary Exercise Test, 6-Minute Walk Test, and Quadriceps Strength.
abstract: BACKGROUND
  Exercise testing is part of the regular assessment of patients with cystic fibrosis (CF). We aimed to evaluate (1) the convergent validity of the 1-min sit-to-stand (STS) test in CF by investigating its relationships with peak oxygen uptake (peak V̇O2), quadriceps strength, and quality of life and (2) to compare these associations with those of the 6-min walk test (6MWT).
  
  
  METHODS
  Twenty-five adults with CF (FEV1= 59 ± 24%) performed the STS test, the 6MWT, quadriceps strength assessment, and cardiopulmonary exercise test (CPET). Physical activity level, quality of life, and self-esteem were assessed by questionnaires.
  
  
  RESULTS
  STS repetitions, 6-min walk distance, quadriceps strength, and peak V̇O2were, respectively, 71 ± 12, 90 ± 10, 93 ± 29, and 62 ± 16% of predicted. The STS test had moderate associations with peak V̇O2(r = 0.56, P = .004), quadriceps strength (r = 0.52, P = .008), and some questionnaire items (eg, perceived physical strength, r = 0.67, P < .001) only when repetitions were expressed as a product of body weight. Overall, these associations were weaker than those obtained from 6-min walk distance × weight. Oxygen desaturation during the STS test was strongly associated with oxygen desaturation during CPET (r = 0.80, P < .001). Peak heart rate was lower during the STS test as compared with CPET (P < .001) and the 6MWT (P = .009).
  
  
  CONCLUSIONS
  The STS test cannot be used as a replacement for CPET to accurately assess peak exercise capacity in CF. The STS test may have utility in detecting patients with CF who may exhibit a high level of oxygen desaturation during heavy exercise. Further studies should identify the factors contributing to STS performance to confirm the potential interest of STS repetitions × body weight outcome as a useful submaximal exercise parameter in CF.
authors.affiliation: Université de Nice Sophia Antipolis, Université de Toulon, Laboratoire Motricité Humaine Education Sport Santé, Toulon, France. gruet@univ-tln.fr.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Gruet
authors.affiliation: Exercise Research Laboratory, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Leonardo Alexandre
authors.initials: LA
authors.lastname: Peyré-Tartaruga
authors.affiliation: Université de Nice Sophia Antipolis, Université de Toulon, Laboratoire Motricité Humaine Education Sport Santé, Toulon, France.|Centre de Ressources et de Compétences de la Mucoviscidose (CRCM), Hôpital Renée Sabran, Giens, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Mely
authors.affiliation: Université de Nice Sophia Antipolis, Université de Toulon, Laboratoire Motricité Humaine Education Sport Santé, Toulon, France.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Vallier
mesh_terms: D000293:Adolescent; D000328:Adult; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D010101:Oxygen Consumption; D011187:Posture; D052097:Quadriceps Muscle / Q000503:physiopathology*; D011788:Quality of Life; D015203:Reproducibility of Results; D013997:Time Factors; D000070857:Walk Test / Q000379:methods; D055815:Young Adult
keywords: cystic fibrosis; exercise test; limb muscle function; peak oxygen uptake; quality of life; rehabilitation