Conclusion Neither HIIT nor MICT is superior for altering TC , TRG , or LDL-C , or TC-HDL-C ratio .
To raise HDL-C , HIIT may result in a larger effect size compared with MICT .
Objective To compare the effects of moderate intensity continuous training ( MICT ) and high intensity interval training ( HIIT ) on  adult lipid profiles ;  to identify training or participant characteristics that may determine exercise-induced change in total cholesterol ( TC ) , triglycerides ( TRG ) , high-density lipoprotein cholesterol ( HDL-C ) and low-density lipoprotein cholesterol ( LDL-C ) .
Novel all-extremity high-intensity interval training improves aerobic fitness, cardiac function and insulin resistance in healthy older adults
Aging is associated with decreased aerobic fitness and cardiac remodeling leading to increased risk for cardiovascular disease . High-intensity interval training ( HIIT ) on the treadmill has been reported to be more effective in ameliorating these risk factors compared with moderate-intensity continuous training ( MICT ) in patients with cardiometabolic disease . In older adults , however , weight-bearing activities are frequently limited due to musculoskeletal and balance problems . The purpose of this study was to examine the feasibility and safety of non-weight-bearing all-extremity HIIT in older adults . In addition , we tested the hypothesis that all-extremity HIIT will be more effective in improving aerobic fitness , cardiac function , and metabolic risk factors compared with all-extremity MICT .  Fifty-one healthy sedentary older adults ( age : 65±1years ) were r and omized to HIIT ( n=17 ) , MICT ( n=18 ) or non-exercise control ( CONT ; n=16 ) . HIIT ( 4 × 4min 90 % of peak heart rate ; HRpeak ) and isocaloric MICT ( 70 % of HRpeak ) were performed on a non-weight-bearing all-extremity ergometer , 4 × /week for 8weeks under supervision . All-extremity HIIT was feasible in older adults and result ed in no adverse events . Aerobic fitness ( peak oxygen consumption ; VO2peak ) and ejection fraction ( echocardiography ) improved by 11 % ( P<0.0001 ) and 4 % ( P=0.001 ) , respectively in HIIT , while no changes were observed in MICT and CONT ( P≥0.1 ) . Greater improvements in ejection fraction were associated with greater improvements in VO2peak ( r=0.57 ; P<0.0001 ) . Insulin resistance ( homeostatic model assessment ) decreased only in HIIT by 26 % ( P=0.016 ) . Diastolic function , body composition , glucose and lipids were unaffected ( P≥0.1 ) . In conclusion , all-extremity HIIT  is feasible and safe  in older  adults  . HIIT , but not MICT  , improved aerobic fitness , ejection fraction , and insulin resistance
Conclusion Neither HIIT nor MICT is superior for altering TC , TRG , or LDL-C , or TC-HDL-C ratio .
To raise HDL-C , HIIT may result in a larger effect size compared with MICT .
Objective To compare the effects of moderate intensity continuous training ( MICT ) and high intensity interval training ( HIIT ) on  adult lipid profiles ;  to identify training or participant characteristics that may determine exercise-induced change in total cholesterol ( TC ) , triglycerides ( TRG ) , high-density lipoprotein cholesterol ( HDL-C ) and low-density lipoprotein cholesterol ( LDL-C ) .