WORKLOAD INDEXED BLOOD PRESSURE RESPONSE TO RAMP EXERCISE ABOVE AND BELOW CRITICAL POWER

Authors

Collen J. McLain, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA
Coleman Honea, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA
Petra Kis, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA
Colin W. Kipper, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA
Kylie N. Sears, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA
Kilyn D. Fredickson, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA
Shane M. Hammer, School of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, USA

Abstract

A ramp exercise test performed to task failure includes intensities spanning three exercise intensity domains with distinct metabolic and cardiovascular characteristics. Previous studies suggest the overall workload-indexed systolic blood pressure response to ramp exercise (ΔSBP/ΔWatt) might help identify individuals at risk of developing hypertension. PURPOSE: To test the hypothesis that ΔSBP/ΔW is distinct across exercise intensity domains and differs from the overall ΔSBP/ΔWatt response. METHODS: Eight healthy participants (22 ± 4 yrs; 6F/2M) performed a ramp incremental test (20W/min) on a cycle ergometer until task failure followed by a 3-min all-out test with maximal effort. Peak power (Ppeak) was determined as the highest power output reached during the ramp test. Critical power (CP) was estimated using the average power during the final 20s of the all-out test. Pulmonary gas exchange was measured by an open-circuit analyzer and gas exchange threshold (GET) was determined using the V-slope method. Beat-by-beat blood pressure was measured at baseline and throughout the test by finger plethysmography which was calibrated to brachial arterial pressure. Exercise intensity domains were determined for each subject as moderate (MODCP). The ΔSBP/ΔW was calculated for each participant for the overall test (OVR) and within each intensity domain. Comparisons were made across domains and with OVR using a one-way repeated-measures ANOVA and Tukey’s tests. RESULTS: Maximal oxygen uptake was 32.6 ± 7.1 mL/min/kg. Ppeak was 204 ± 43.4 W. GET was 131 ± 37 W (61 ± 11% Ppeak). CP was 168 ± 51 W (81 ± 10% Ppeak). ΔSBP from baseline was 30.5 ± 27.7 mmHg. The OVR ΔSBP/ΔW was 0.19 ± 0.08 mmHg/W. There was a significant effect of intensity domain on ΔSBP/ΔW (p < 0.05). The ΔSBP/ΔW within MOD (0.21 ± 0.09) was not different than OVR (p = 0.86). The ΔSBP/ΔW within HVY (0.34 ± 0.09) was greater than OVR (p < 0.05) and MOD (p < 0.01). The ΔSBP/ΔW within SEV (0.19 ± 0.08) was not different than OVR (p = 0.14). CONCLUSION: The ΔSBP/ΔW changed according to intensity domain which may reflect their distinct physiological characteristics. Future studies should investigate whether domain-specific ΔSBP/ΔW better predicts adverse cardiovascular outcomes compared to the overall response to ramp exercise.

Recommended Citation

McLain, Collen J.; Honea, Coleman; Kis, Petra; Kipper, Colin W.; Sears, Kylie N.; Fredickson, Kilyn D.; and Hammer, Shane M. (2025) "WORKLOAD INDEXED BLOOD PRESSURE RESPONSE TO RAMP EXERCISE ABOVE AND BELOW CRITICAL POWER," International Journal of Exercise Science: Conference Proceedings: Vol. 11: Iss. 12, Article 83.
Available at: https://digitalcommons.wku.edu/ijesab/vol11/iss12/83