Umm...
because Bardock turned super saiyan? Also that he was real strong by the time he went back in time (I could have sworn I read that his power level was around 10,000 at the time he "died". Him surviving that incident and healing should've added to his strength). Also assuming that at the time of friezas ancestors, they werent as strong since there wouldnt have been the need to be. The were strong enough to wipe out planets so any extra strength would have been unnecessary. Maybe pure luck that he could have beaten Chilled with a single Ki blast.
I assume.
because Bardock turned super saiyan? Also that he was real strong by the time he went back in time (I could have sworn I read that his power level was around 10,000 at the time he "died". Him surviving that incident and healing should've added to his strength). Also assuming that at the time of friezas ancestors, they werent as strong since there wouldnt have been the need to be. The were strong enough to wipe out planets so any extra strength would have been unnecessary. Maybe pure luck that he could have beaten Chilled with a single Ki blast.
I assume.