With aging and disease, there is a breakdown of the natural fractal-like organization of heart rate (HR). Fractal-like correlation properties of HR can be assessed with detrended fluctuation analysis (DFA). A short-time scaling exponent (_s) value of 1 is associated with healthy HR dynamics while values that deviate away from one, in either direction, indicate fractal collapse. The purpose of this study was to examine the effect of resistance exercise training (RT) on fractal correlation properties of HR dynamics. Resting ECG was collected at baseline, following a 4-week time control period and 6-weeks of RT (3 days per week) in thirty-four men (23 ± 1 years of age). Fractal properties of HR were assessed with DFA. There was no change in _s following either the time control period or RT (1.01 ± 0.06 to 0.98 ± 0.06 to 0.93 ± 0.04, p>0.05). Given the potential bi-directional nature of fractal collapse, subjects were retrospectively separated into two groups (higher _s and lower _s) based on initial _s using cluster analysis. An interaction was detected for &#945;s following RT (p<0.05). There was no change in _s in either group following the time control but &#945;s increased following RT in the lower _s group (n=18: 0.73 ± 0.04 to 0.69 ± 0.04 to 0.88 ± 0.04) and _s decreased following RT in the higher _s group (n=16: 1.20 ± 0.04 to 1.24 ± 0.04 to 0.98 ± 0.04). In conclusion, RT improves fractal properties of HR dynamics.