Validation of a New Ramping Aerobic Exercise Protocol (NDKS) in Overweight, Obese, and Normal Weight Individuals

The research purpose was to establish reliability and validity of determining VO_2max via a new NDKS (Nustad Dressler Kobes Saghiv; named for the sir names of department faculty at the time) ramping protocol compared to the Standard Bruce protocol in normal weight, overweight, and obese individuals. Forty-two physically active participants (23M, 19F) ages 18-28 years were grouped into normal weight (N = 15, 8F, BMI 18.5-24.9 kg/m²), overweight (N = 27, 11F, BMI = 25-29.9 kg/m²), and Class I obese (N = 7, 1F, BMI = 30-34.9 kg/m²). Blood pressure, heart rate, blood lactate, respiratory exchange ratio, test duration, rate of perceived exertion, and preference via survey were analyzed during each test. Test-retest reliability of the NDKS was determined first, via tests scheduled one week apart. The NDKS was then validated by comparison with results of the Standard Bruce protocol; tests also conducted one week apart. The normal weight group's Cronbach's Alpha was .995 for absolute VO_2max (L/min) and .968 for relative VO_2max (mL/kg·min). Overweight/obese Cronbach's Alpha for absolute VO_2max (L/min) was .960 and for relative VO_2max (mL/kg·min) .908. Relative VO_2max was slightly higher with NDKS and test time lower compared to the Bruce (p < .05). 92.3% of subjects identified more localized muscle fatigue with the Bruce protocol vs NDKS. The NDKS is a reliable and valid exercise test which can be used to determine VO_2max in physically active, young normal weight, overweight and obese individuals.