Velocity-based training (VBT), a unique resistance-training technique used by high-level athletes, uses velocity rather than load for progression. No study has examined the effects of VBT on upper body (chest press) strength (1-repetition maximum: CP-1RM), peak power (CP-PP), or power (CP-PPAsym) and velocity asymmetries (CP-PVAsym) between the more-affected and less-affected sides in Parkinson’s disease (PD) patients. PURPOSE: To assess changes in each variable following VBT at 10% and 30% velocity loss thresholds (VLT) in 15 PD patients. METHODS: CP-1RM, and CP-PP, CP-PPAsym and CP-PVAsym at 40 - 80%1RM, were analyzed using 2 (VLT group) x 5 (load) x 2 (time) repeated measures ANOVAs with LSD pairwise comparisons. Results were reported as mean difference ± standard error, p-values and Hedge’s g. RESULTS: For 1RM, a time effect was observed (F(1, 13)=18.243, p<.001, ηp2=.584) with a pairwise comparison revealing a significant increase (5.250±1.229kg; 2.595kg, 7.905kg; p<.001; g=0.38). For CP-PPAsym there was a significant load x group interaction (F(4,52)=2.91, p=0.03, ηp2=0.183) with significantly greater symmetry at 80%1RM for 10%VLT than 30%VLT (0.091± 0.024; 0.039, 0.144W; p=0.002; g=1.51). For CP-PVAsym, there was a significant main effect for time (F(1,13)=13.02, p=0.003, ηp2=0.500) with pairwise comparison showing a significant improvement (0.078 ± 0.022; 0.031, 0.1251; p=0.003; g=0.85) driven by the 10% VLT group (0.118 ± 0.034; 0.045, 0.190; p=0.004; g=1.21). Although no improvements were seen in CP-PP, these results indicate that VBT can improve upper body strength, and can positively affect strength and upper body asymmetries, especially at a lower VLT,  in people with PD.