Effect of High-intensity Intermittent Sprinting on Appetite Control on Obese Volunteers
Effect of High-intensity Intermittent Sprinting on Appetite Control on Obese Volunteers
Several studies have shown that high intensity intermittent sprints (HIIS) are more effective
 than moderate intensity continuous cycling (MICC) in reducing fat mass and improving insulin
 resistance in normal weight individuals. Changes in the appetite-regulatory system in
 response to exercise are likely to explain, at least partially, the better outcome observed
 after HIIS. Unfortunately, there are no studies comparing the impact of different types of
 acute aerobic exercise on the release of appetite-regulating hormones, subjective feelings of
 appetite and subsequent energy intake (EI).

 The primary objective of this study is to investigate the effects of acute isocaloric bouts
 of HIIT and MICC or a short duration sprint, in comparison with a resting control condition,
 on the postprandial release of appetite-regulating hormones, subjective feelings of appetite
 and subsequent EI in obese individuals. The investigators hypothesize that an isocaloric
 session of HIIS will result in a better short-term appetite control compared with MICC, by
 reducing hunger feelings and subsequent food intake more than MICC and by inducing a larger
 increase in the release of satiety gut peptides compared with the MICC.
This will be a randomised cross-over study with four legs. Participants will act as their own
 controls and will be assigned to the four experimental conditions (resting, HIIS, MICC and
 SDS), 1 week apart, in a counter-balanced order.

 Participants will be asked to come to the Unit five times: one preliminary session and four
 experimental conditions (resting, HIIS and MICC isocaloric sessions and SDS). In the
 preliminary session, anthropometric data (weight and height) will be collected and a maximal
 fitness test performed, using a cycle ergometer.

 For the four experimental conditions, participants will be asked to arrive at approximately
 8.00, having fasted for at least 10 hours, and a cannula will be inserted into an antecubital
 vein. Two fasting blood samples will be taken and a standard breakfast offered. After that,
 serial blood samples will be taken at regular intervals for a period of 3h.

 Participants will be asked to rate their subjective feelings of hunger and fullness using
 visual analogue scales (VAS) throughout each study morning at different time points. Three
 hours after breakfast, participants will be placed in individual rooms, presented with a
 standardized lunch and instructed to rate the taste and palatability of the food presented.
Inclusion Criteria:

 -  an inactive lifestyle,

 -  weight stable on the previous 3 months,

 -  not currently dieting to loose weight

 -  restraint score derived from the Three Factor Eating Behaviour Questionnaire ≤12

 Exclusion Criteria:

 -  history of coronary heart disease,

 -  type 1 or type 2 diabetes,

 -  anaemia,

 -  gout,

 -  depression or other psychological disorders,

 -  eating disorders,

 -  drug or alcohol abuse within the last two years,

 -  current medication known to affect appetite or induce weight loss and hypertension.