Frail ElderlyGeriatric AssessmentProspective StudiesFollow-Up StudiesTime FactorsTreatment OutcomeLongitudinal StudiesRisk FactorsAgingCohort StudiesBiological MarkersIndependent LivingDouble-Blind MethodMuscle WeaknessActivities of Daily LivingPredictive Value of TestsQuestionnairesProportional Hazards ModelsHealth StatusSeverity of Illness IndexAnalysis of VarianceBlood PressureQuality of LifeDisease ProgressionC-Reactive ProteinIncidenceRisk AssessmentAssisted Living FacilitiesMultivariate AnalysisPilot ProjectsDisabled PersonsMobile ApplicationsMobility LimitationHand StrengthLinear ModelsGeriatricsCross-Sectional StudiesLogistic ModelsFatigueExerciseUnited StatesMotor ActivityRegression AnalysisPrognosisPrevalenceBaltimoreWeight LossResidence CharacteristicsHeart RateAstheniaComorbidityDisability EvaluationChronic DiseaseLethargyAge FactorsCross-Over StudiesPlacebosBody Mass IndexDose-Response Relationship, DrugDrug Therapy, CombinationHousing for the ElderlyDepressionRetrospective StudiesCognition DisordersSex FactorsHemodynamicsCardiovascular DiseasesStatistics, Nonparametric