The BariEX Study

• Research type

  Research Study

• Full title

  The effect of acute aerobic exercise on the time spent in hypoglycaemia after bariatric surgery

• IRAS ID

  286897

• Contact name

  Dimitris Papamargaritis

• Contact email

  dimitris.papamargaritis@uhl-tr.nhs.uk

• Sponsor organisation

  University of Leicester

• ISRCTN Number

  ISRCTN17674908

• Duration of Study in the UK

  1 years, 11 months, 30 days

• Research summary

  Bariatric surgery is the most effective method to achieve significant long-term weight loss and weight maintenance in patients with severe and complex obesity. Roux-en-Y gastric bypass (RYGB) is the most commonly performed bariatric surgery procedure worldwide. Common long-term complications can occur after RYGB, such as nutritional and vitamin deficiencies, early dumping syndrome (food moving faster than normal into the small intestine and absorbed faster than normal) and low sugar levels (hypoglycemia) one to three hours after meals. Individuals who experience post-meal hypoglycaemia after RYGB produce more than the typically required amounts of insulin after their meal. Research suggests that aerobic exercise AEX after RYGB enhances insulin sensitivity in individuals without type two diabetes mellitus, a risk factor of hypoglycaemia.

  Exercise after RYGB is a complementary and necessary therapy which elicits beneficial health effects, such as improvements in fitness, quality of life, functional ability, body composition, and may help prevent weight-regain and co-morbidities returning in this population. There is currently no evidence based physical activity guidelines for individuals whom have undergone bariatric surgery. European guidelines for post-bariatric surgery management recommend that patients should adhere to a healthy lifestyle including moderate intensity AEX for at least 30 minutes/day. This study will investigate whether a single 30 minute bout of AEX, in individuals post RYGB surgery, increases the time spent in hypoglycaemia over the preceding 24-hours.

  Participants will be randomised to one of the following sequences:

  AEX intervention: prolonged sitting for ≈6 hours (h) 15 minutes (min) punctuated by 30min AEX performed at 60% VO2 peak
  Control: prolonged sitting for ≈6h 45min

  Group 1) Control x intervention
  or
  Group 2) Intervention x control

  The expected study duration is approximately 1 month per participant. Participants will attend six visits in total.

  Summary of results
  People who have undergone weight loss surgery (also called bariatric or metabolic surgery) can sometimes experience a condition called post-bariatric hypoglycaemia. This happens when blood sugar levels drop too low, usually 1 to 3 hours after eating a meal high in carbohydrates (like sugars and starches). It occurs because, after surgery, food can move quicker than normal through the digestive system. This can cause sugar to be absorbed too fast and lead to the body releasing too much insulin, the hormone that helps lower blood sugar. As a result, blood sugar may fall too low a few hours later.

  Symptoms can include sweating, shakiness, tiredness, dizziness, or difficulty concentrating. In severe cases, it may lead to fainting or accidents. There are few effective treatments for hypoglycaemia. People are often advised to follow a long-term low-carbohydrate diet, but more effective solutions are needed.

  Exercise is widely recommended after weight loss surgery because it improves fitness, supports long-term weight loss maintenance, and helps with physical and mental health. However, exercise can increase how sensitive the body is to insulin; therefore, experts have wondered whether it might also increase the risk of low blood sugar in people prone to post-bariatric hypoglycaemia.

  What was this study about?
  This study looked at how a single session of moderate-intensity aerobic exercise, 30 minutes of brisk walking on a treadmill, affects blood sugar levels in people at least one year after undergoing weight loss surgery . All participants were adults without diabetes.

  On one day, they sat for most of the morning, with no exercise before lunch. The other day, they also spent most of the morning sitting, but completed a 30-minute brisk walk before lunch.

  Lunch on both days was a standardised meal (called a mixed meal tolerance test), designed to assess how the body responds to food. All participants ate the same meals at the same times throughout the day, and wore continuous glucose monitor devices to track blood sugar levels over a 24-hour period.

  What did the study find?
  Very few participants had low blood sugar episodes on either day, and the exercise did not increase the risk of hypoglycaemia. In fact, after exercising, participants had more stable blood sugar levels throughout the day, with fewer sharp rises and falls.

  Interestingly, those who exercised before lunch had slightly higher blood sugar levels after eating their lunch, compared to when they didn’t exercise. This may reflect changes in how the body processes food after physical activity, such as digestion speed or insulin response, though the exact reasons are still unclear.

  What does this mean?
  This study suggests that doing 30 minutes of moderate intensity aerobic exercise before a meal is safe in people who have had weight loss surgery and do not have diagnosed post-bariatric hypoglycemia. It may even help promote steadier blood sugar levels throughout the day.

  More research is needed, especially in people with frequent or severe low blood sugar episodes, but these findings support the idea that moderate exercise can be part of a safe and healthy routine after weight loss surgery.

• REC name

  London - Bromley Research Ethics Committee

• REC reference

  21/LO/0404

• Date of REC Opinion

  30 Jun 2021

• REC opinion

  Further Information Favourable Opinion