This study aimed to determine the relationships between internal training load (session-RPE) and wellness status (delayed onset muscle soreness – DOMS, stress, fatigue, and sleep quality) on both daily and weekly bases over a basketball season. Fifteen professional basketball players provided their wellness status and perceived training load for all training sessions and matches over a season. Daily correlations were based on the perceived load of a training session/match and the wellness status rated on the following day (before the next session). Weekly correlations were based on the sum of all ratings of the week for each variable. Results showed that DOMS and fatigue presented higher correlations with session-RPE than stress and sleep quality on both daily and weekly analyses. Daily measures presented small-to-moderate correlations between the perceived training load and wellness categories over the months. Weekly correlations increased (moderate-tolarge) for all wellness categories, except for stress. We concluded that DOMS and fatigue are more associated to session-RPE than stress and sleep quality in professional basketball players. Weekly analyses may help coaches to better understand the impact of training load on athletes’ physical wellness (DOMS and fatigue), possibly due to a delayed physiological response to training load.