Endurance and Sprint Training Improve Glycemia and V˙O2peak but only Frequent Endurance Benefits Blood Pressure and Lipidemia

Abstract

Purpose: Sprint interval training (SIT) has gained popularity as a time-effective alternative to moderate-intensity endurance training (END). However, whether SIT is equally effective for decreasing cardiometabolic risk factors remains debatable, as many beneficial effects of exercise are thought to be transient, and unlike END, SIT is not recommended daily. Therefore, in line with current exercise recommendations, we examined the ability of SIT and END to improve cardiometabolic health in overweight/obese males. Methods: Twenty-three participants were randomized to perform 6 wk of constant workload SIT (3 d•wk −1 , 4-6 Â 30 s ~170% W peak , 2 min recovery, n = 12) or END (5 d•wk −1 , 30-40 min, ~60% W peak , n = 11) on cycle ergometers. Aerobic capacity (V ˙O2peak ), body composition, blood pressure (BP), arterial stiffness, endothelial function, glucose and lipid tolerance, and free-living glycemic regulation were assessed pre-and posttraining. Results: Both END and SIT increased V ˙O2peak (END ~15%, SIT ~5%) and glucose tolerance (~20%). However, only END decreased diastolic BP, abdominal fat, and improved postprandial lipid tolerance, representing improvements in cardiovascular risk factors that did not occur after SIT. Although SIT, but not END, increased endothelial function, arterial stiffness was not altered in either group. Indices of free-living glycemic regulation were improved after END and trended toward an improvement after SIT (P = 0.06-0.09). However, glycemic control was better on exercise compared with rest days, highlighting the importance of exercise frequency. Furthermore, in an exploratory nature, favorable individual responses (V ˙O2peak , BP, glucose tolerance, lipidemia, and body fat) were more prevalent after END than low-frequency SIT. Conclusion: As only high-frequency END improved BP and lipid tolerance, free-living glycemic regulation was better on days that participants exercised, and favorable individual responses were consistent after END, high-frequency END may favorably improve cardiometabolic health.

The impact of high-intensity interval training on vascular function in adults: A systematic review and meta-analysis

“…The mean age of participants ranged from 21 ( 65 ) to 75 years ( 79 ) and the mean BMI of participants ranged from 21 ( 65 ) to 37 kg/m 2 ( 66 ). Both males and females were included in the majority of studies ( 44 – 48 , 50 – 53 , 55 , 57 – 61 , 64 , 65 , 68 – 77 , 79 ), females only in five studies ( 49 , 62 , 63 , 66 , 67 ), and males only in two studies ( 54 , 78 ). In the meta-analysis, participant health status varied regarding health and disease status, and included overweight and obesity, metabolic syndrome, prediabetes, type 2 diabetes, type 1 diabetes, polycystic ovarian syndrome, hypertension, heart failure, coronary artery disease, myocardial infarction, repaired tetralogy of Fallot (open heart surgery), and heart transplant.…”

“…In the meta-analysis, participant health status varied regarding health and disease status, and included overweight and obesity, metabolic syndrome, prediabetes, type 2 diabetes, type 1 diabetes, polycystic ovarian syndrome, hypertension, heart failure, coronary artery disease, myocardial infarction, repaired tetralogy of Fallot (open heart surgery), and heart transplant. In addition, in subgroup analyses, obesity, type 2 diabetes, polycystic ovarian syndrome, type 1 diabetes, prediabetes, and the metabolic syndrome were included together as metabolic disorders ( 45 , 48 , 50 , 54 , 58 , 59 , 62 , 63 , 66 , 67 , 69 , 70 , 72 – 74 , 77 ), and coronary artery disease, myocardial infarction, repaired tetralogy of Fallot, hypertension, heart failure, and heart transplant were included as cardiovascular diseases ( 44 , 46 , 47 , 51 , 52 , 57 , 60 , 61 , 68 , 71 , 75 , 76 , 79 ). If participants did not have any chronic disorders, they were included as free of cardiometabolic diseases ( 49 , 53 , 55 , 56 , 64 , 65 , 78 ) and full details of participant characteristics are shown in Table 1 .…”

“…After reviewing the full-texts, 93 studies were excluded according to the reasons presented in Figure 1. Finally, 36 studies met all eligibility criteria and were included in the meta-analysis, of which 18 studies compared HIIT vs. MICT (44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59)(60)(61), 10 studies compared HIIT vs. CON (62)(63)(64)(65)(66)(67)(68)(69)(70)(71), and 8 studies compared HIIT vs. CON and MICT (72)(73)(74)(75)(76)(77)(78)(79). In addition, only one included study used a crossover design (57).…”

“…Frequency of training ranged from 2 to 6 sessions pre week, with 3 sessions per week being the most common. Of the 26 studies that directly compared HIIT vs. MICT (44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58)(59)(60)(61)(72)(73)(74)(75)(76)(77)(78)(79), 17 studies clearly reported that HIIT protocols were matched with MICT protocols based on energy, time, duration, and/or total work performed (45, 47,48,50,52,53,56,57,59,61,[73][74][75][76][77][78][79]. MICT protocols included MICT at 50-75% HRmax, HRR, or VO 2 peck/max with durations ranging from 15 to 60 min.…”

Physiological Adaptations to High-Intensity Interval Training Combined with Blood Flow Restriction in Masters Road Cyclists

“…However, there were no significant differences between groups. HIIT has been shown to be efficacious in improving endothelial function more than moderate-intensity continuous training in previously sedentary middle-age and older adults (43,44), although conflicting findings have been reported (45). The present study is unique as our focus was placed on masters athletes in general and on road cyclists in particular.…”