Spondylitis, AnkylosingSpondylitisExercise TestExercise TherapyHLA-B27 AntigenExerciseExercise ToleranceSacroiliac JointPhysical ExertionSpineSpondylarthritisAntirheumatic AgentsOxygen ConsumptionPhysical EnduranceSpondylarthropathiesSeverity of Illness IndexMuscle, SkeletalArthritisBlood SedimentationIritisTuberculosis, SpinalArthritis, ReactiveArthritis, PsoriaticRheumatic DiseasesTreatment OutcomeBalneologyHeart RateBicyclingUveitis, AnteriorRestLumbar VertebraePhysical FitnessKyphosisArthritis, RheumatoidResistance TrainingThoracic VertebraeTime FactorsRunningAnaerobic ThresholdMuscle Stretching ExercisesPulmonary Gas ExchangeHLA AntigensLactic AcidBack PainCervical VertebraeAnti-Inflammatory Agents, Non-SteroidalImmunoglobulin GOsteitisSulfasalazineReceptors, Tumor Necrosis FactorPseudarthrosisSpinal DiseasesBreathing ExercisesDouble-Blind MethodSacroiliitisAntibodies, MonoclonalTumor Necrosis Factor-alphaKlebsiellaPsoas Abscess