How is affective well-being related to need satisfaction and frustration across rehabilitation in injured athletes? Findings from an intensive longitudinal study.

Injuries are common in competitive sports and often lead to uncertainty about athletes' future participation. During rehabilitation, athletes face challenges that hinder their basic psychological needs for autonomy, competence, and relatedness, often associated with poorer affecting well-being. While prior research has demonstrated links between higher need frustration, lower need satisfaction, and poorer well-being, most studies have been cross-sectional, thereby missing dynamic fluctuations throughout rehabilitation. This intensive longitudinal study aimed to assess these within-person relationships between need satisfaction, need frustration, and affective well-being in injured athletes, as well as examine potential within-person cross-lagged effects. The study involved 103 injured athletes who completed assessments three times daily over 21 days, resulting in 3074 observations. Using multilevel modeling, the analysis found that 36-45 % of variance in affective well-being, need satisfaction, and need frustration was between individuals, while 55-64 % stemmed from within-person fluctuations. Higher need satisfaction and lower need frustration were linked consistently to better affective well-being at both the within- and between-person levels. However, few significant within-person cross-lagged effects were found. These findings emphasize the need to address both within-day variations and overall levels of psychological needs during rehabilitation. While the study confirmed the strong association between need satisfaction, need frustration, and affective well-being, further research is needed to establish causal relationships. Ideally, future studies should incorporate a higher frequency of measurements per day to examine feedback mechanisms between these variables during rehabilitation.