The Method For Cardiorespiratory Fitness Testing And Training Based On The Intelligent Cycle Ergometer

Cardiorespiratory fitness(CRF)represents the capacity of the body to sustain the physical activity.The whole process involves the ability of the heart to pump the blood and the lung to intake the oxygen,which reflects the level of cardiopulmonary reserve function under certain exercise intensity.CRF is acted as one of the five vital signs parameters along with the respiration,temperature,pulse and blood pressure and it is recognized as an important predictive index for decreasing cardiovascular disease and death risk.The most effective approach for increasing the cardiopulmonary function capacity and decreasing the risk of disease among general populations is to implement the CRF evaluation test and develop a scientific and effective training program according to the evaluation result.However,recently,this kind of CRF health management approach is not well-popularized in public health field,the main reasons are as follows:(1)the device for assessing CRF is dependent on import,and it is very expensive,mostly owned by the professional sports colleges and medical rehabilitation institutions who have the financial ability to afford these devices;(2)the method for CRF direct measurement is time-consuming,and difficult to implement the test.Meanwhile,the predictive accuracy of the indirect method for assessing CRF is not ensured;(3)the subjective factors of human subjects may lead to the unaccuracy control of exercise parameters during testing and training,therefore,the validity of the testing and training can not be ensured.According to the above requirements,firstly,this dissertation is based on the development of the cycle ergometer CRF evaluation system,and subsquently,the dissertation is focused on the key techniques in CRF testing and training and the aspects for increasing the validity for CRF testing and training methods.The main research contents are as follows:1.Construction of the intelligent cycle ergometer CRF evaluation systemFirstly,we designed two different cycle ergometers based the comparison and analysis of the advantages and disadvantages of two different exercise modalities of linear reciprocating motion and circular reciprocating motion.Secondly,in order to meet the requirement for constant workload control during CRF testing,we solved this constant workload control problem with no affects by pedaling rate over certain range by applying fuzzy PID control algorithm.The control accuracy is higher and the control error is lower.Finally,we constructed the intelligent cycle ergometer CRF evalution system with the function of constant workload control,combined with the design of heart rate measurement unit and intelligent CRF testing and evaluation software.This system can accurately analyze and assess the exercise cardiopulmonary reserve capacity of the subjects and provide a comprehensive testing and evaluation report.2.The study on the validity of the intelligent cycle ergometer CRF evalution systemIn this study,the correlation and agreement of the HRmax and VO2max measured results between our self-development system and the "golden standard"Monark cycle ergometer CRF evalution system were compared during maximal exercise testing experiments.The results indicated a strong correlation(HRmax:r=0.853,VO2max:r=0.892)and an narrow limits of agreement(HRmax LoA:-6.8bpm-4.6bpm,VO2max LoA:-5.7 ml·kg-1 · min-1-4.9 ml·kg-1·min-1),and no significant differences(p>0.05)of the stage heart rate HRstage and stage oxygen uptake VO2stage before subjects reached their physiological limit were found between the two CRF evalution systems.The results showed the validity of our self-development system for assessing CRF.3.The study of the submaximal exercise test for assessing CRF based on the exercise parametric modelIn this study,considering the nonlinear part of the exercise parametric model between the exercise workload(W),exercise heart rate(HR)and oxygen uptake(VO2),we proposed a two-stages customed submaximal exercise test(TC-SMT)for predicting VO2max based on the partition of exercise workload according to the exist of the lactate threshold(LT).The LT threshold was selected as the partition basis of the two stages of the workload because there exists a nonlinear relationship after LT threshold between the VO2-W and HR-W.The amout of the two-stage exercise workload can be predicted by the VO2max non-exercise parametric regression model and the VO2-W metabolic equation.In comparison with the traditional YMCA submaximal exercise test,the result showed a higher correlation(r=0.89),a lower standard error of the estimate(SEE=3.11 ml·kg-1·min-1)and a better limit of agreement(LoA:-6.9 ml·kg-1 · min-1-5.3 ml· kg-1· min-1)for the TC-SMT VO2max predicted result compared with the GXT VO2max measured result,which improved the accuracy of the submaximal exercise test for assessing CRF.4.The study on the training method for improving CRF based on the exercise intensity control.(1)The study on exercise intensity evaluation method based on the heart rate controlThe accurate evaluation of the exercise intensity is the premise and foundation for the implementation of a CRF training program,and heart rate is a common-used evaluation indicator for the exercise intensity.In this study,we proposed an exercise intensity evaluation method based on the heart rate feedback control,which accurately monitoring exercise intensity through the tracking of the target heart rate.Firstly,we established the identification model of the heart rate response during cycle ergometer exercise testing using system identification method,which was based on the study and analysis of the heart rate kinetic response characteristics during exercise testing.Secondly,we designed a heart rate feedback controller using the RST control strategy to track the target heart rate.And finally,experiments were conducted to test and assess the heart rate control performance.The results presented that,the average value of the root-mean-square error for tracking target heart rate under two different intensities were both lower than 3.5bpm,which reflected the accurate evaluation of the exercise intensity.(2)The study on different exercise intensity modes for improving CRFSelecting the appropriate exercise intensity training mode is the key factor for improving CRF.Based on the established techniques and methods from the above research,a precise CRF training guidance procedure was constructed and the validity and physiological mechanism of two different exercise intensity modes(MICT and HIIT)were discussed and analyzed through exercise intervention experiment.The study indicated that VO2max,body fat percentage(Fat%)and stage heart rate(HRstage)were significantly increased after the exercise intervention.The effectiveness of the CRF improvement was more obvious for HIIT than MICT training mode.Meanwhile,the study also represents that the CRF health management method established in this study is valid and reliable for improving CRF level.