[Effects of intermittent walk program on the body mass and composition in obese women]

High Intensity Long Interval Sets Provides Similar Enjoyment as Continuous Moderate Intensity Exercise. The Tromsø Exercise Enjoyment Study

OBJECTIVE

High intensity interval exercise sessions with interval sets over 3 min may provide superior cardiorespiratory fitness benefits. To our knowledge, the exercise enjoyment of interval sets over 3 min is not yet elucidated. The aim of this study was to examine exercise enjoyment following one session with four intervals of 4 min high intensity exercise (HIIE) versus one session of 45 min moderate intensity continuous exercise (CE) in iso-caloric conditions using a randomized crossover design.

METHODS

Seven young healthy participants were recruited to undergo two different exercise sessions in a randomized order: (1) 4 × 4 min intervals at >90% of maximum heart rate (HR max ) with 3 min of rest between interval sets, and (2) 45 min CE at 70% of HR max . Peak oxygen uptake and HR max were evaluated prior to the experiment. The participants reported their perceived exercise enjoyment using the 18-item physical activity enjoyment scale (PACES) questionnaire and their rating of perceived exertion (RPE) using Borg's 6-20 scale.

RESULTS

There was no difference in the PACES score between the high intensity interval exercise session [median: 95.5 (inter-quartile range: 21.8)] and the moderate intensity CE session [91.0 (13.5), p = 0.36, r = -0.22]. The participants reported a higher RPE in the high intensity interval exercise session [16.5 (2.0)] compared with the CE session [9.0 (2.0), p = 0.01, r = -0.88].

CONCLUSION

Similar exercise enjoyment was reported following four high intensity intervals of 4 min compared with a moderate intensity CE session in this randomized crossover study with iso-caloric conditions. If enjoyment is a mediating factor for engaging in exercise, one should expect a similar probability of exercise adherence following high intensity 4 min intervals and continuous moderate intensity exercise when prescribing aerobic exercise as preventive medicine.

Effects of high vs. moderate exercise intensity during interval training on lipids and adiponectin levels in obese young females

PURPOSE

We investigate the effects of 12-week interval training of moderate- or high-intensity exercise on blood lipids and plasma levels of adiponectin.

METHODS

Thirty-four obese adolescent females [age = 15.9 ± 0.3 years; BMI and BMI-Z-score = 30.8 ± 1.6 kg/m(2) and 3 ± 0.3, respectively], were randomized to high-intensity interval training (HIIT, n = 11), moderate-intensity interval training (MIIT, n = 11), or a control group (CG, n = 12). Maximal oxygen uptake ([Formula: see text]), maximal aerobic speed (MAS), plasma lipids and adiponectin levels were measured in all subjects before and after training.

RESULTS

Following the training program, in both training groups, body mass, BMI-Z-score, and percentage body fat (% BF) decreased, while [Formula: see text] and MAS increased. Low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and adiponectin levels were positively altered (-12.6 and -7.4 %; 6.3 and 8.0 %; 35.8 and 16.2 %; high to moderate training program, respectively). Waist circumference, triglyceride and total cholesterol decreased only in HIIT group (-3.5; -5.3 and -7.0 %, respectively, in all P < 0.05). Significant decrease in the usual index of insulin resistance (HOMA-IR) occurred in HIIT and MIIT groups (-29.2 ± 5.3 and -18.4 ± 8.6 %, respectively; P < 0.01).

CONCLUSION

The results show that HIIT positively changes blood lipids and adiponectin variables in obese adolescent girls, resulting in improved insulin sensitivity, as attested by a lower HOMA-IR, and achieving better results compared to moderate-intensity exercise.