Pretty interesting paper...
It is only looking at a sample size of N=10. They used young, normal weight, untrained, sedentary men. They put 10 subjects on an "Endurance Training (ET)" program (treadmill, 30 minutes per day, 3X per week), 10 subjects on "Resistance Training (RT)" ("max strength", 3 sets, 10 reps, major movements, whole body, 3X per week, increasing weights and decreasing reps), and a control group (CG), that sat on there butts.
They found that the ET group increased VO2 max by 17% and RT group increased by 12% (both values are statistically "significant" increases, and not significantly "different" from each other -- meaning that their sample size is not large enough for them to say that 17% is statistically larger than 12%).
Their conclusion was that ..."whole-body resistance training not only benefits strength but also enhances cardiovascular function." -- meaning that there was significant improvement in cardiovascular fitness alone from only resistance training.
Somebody needs to look at combined RT and ET.
BTW, I'm not saying you should not do cardiovascular (I do), but short of burning calories -- this study suggests it may not do that much for cardiovascular fitness.