Objectives: Swimmers undertake dryland training to improve power and maximise propulsion. Our purpose was to improve strength and quantify transfer to adolescent sprint backstroke and freestyle performances. Methods: Twenty-eight male competitive swimmers participated (age: 12.6±2.6 years; height 156.4±13.4 cm; mass 49.8±15.0 Kg; 50 m freestyle best time 45.0±8.5 s) and were randomized to either dryland strength plus swimming (DS) or a swimming only control group (CONT). The 8 week dryland programme (3 days/week) consisted of 8–10 exercises per session (22 exercises in total) with predominantly 1–2 sets of ~10–20 repetitions. Pre, mid and post 8 weeks training, a strength test battery (countermovement jump, pronated chin ups, isometric forearm and back extension) and 25 m pool testing of backstroke and freestyle was undertaken. Results: DS had greater strength improvements across the test battery (13–167%; ES, 0.51–1.84) than CONT (8-120%; ES, 0.35–2.0) with p<0.05 for 6 of 8 measures. For 50 and 100 m freestyle, DS had greater percentage improvement (DS, 4.8±1.6 and 3.7±1.6%, ES, 0.20 and 0.16; CONT, 2.7±0.9 and 1.6±0.8%, ES, 0.16 and 0.13, p<0.01). There was no between group statistically significant change in backstroke percentage improvement, however both groups displayed small magnitudes of improvements in 50 m and trivial improvements over the 100 m distance (DS, 4.4±2.3 and 1.6±0.5%, ES, 0.29 and 0.08; CONT, 3.6±2.5 and 1.3±0.5%, ES, 0.26, 0.08). Conclusions: Over 8 weeks, adding 90 min dryland training / week to ~7 hour/week swim schedule further improved freestyle ~2.1% and backstroke ~0.5% more than swim training alone.