• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
Breaking Muscle

Breaking Muscle

Breaking Muscle

  • Fitness
  • Workouts
    • Best Shoulder Workouts
    • Best Chest Workouts
    • Best Leg Workouts
    • Best Leg Exercises
    • Best Biceps Exercises
    • Best Kettlebell Exercises
    • Best Back Workouts
    • Best HIIT Workouts
    • Best Triceps Exercises
    • Best Arm Workouts
  • Reviews
    • Supplements
      • Best Pre-Workouts
      • Best Protein Powder
      • Best Whey Protein
      • Best Creatine
      • AG1 Review
    • Equipment
      • Best Adjustable Dumbbells
      • Best Home Gym Machines
    • Certifications
      • ISSA Review
  • News
  • Exercise Guides
    • Legs
      • Back Squat
      • Bulgarian Split Squat
      • Goblet Squat
      • Zercher Squat
      • Standing Calf Raise
      • Hack Squat
    • Chest
      • Bench Press
      • Dumbbell Bench Press
      • Close-Grip Bench Press
      • Incline Bench Press
    • Shoulders
      • Overhead Dumbbell Press
      • Lateral Raise
    • Arms
      • Chin-Up
      • Weighted Pull-Up
      • Triceps Pushdown
    • Back
      • Deadlift
      • Trap Bar Deadlift
      • Lat Pulldown
      • Inverted Row
      • Bent-Over Barbell Row
      • Single-Arm Dumbbell Row
      • Pendlay Row
Fitness

Study Tests Common Ingredient in Weight Loss Pills

New research has analysed the effect of a popular thermogenic aid on the burning of body fat during exercise.

Sam MacIntosh

Written by Sam MacIntosh Last updated on July 26, 2016

New research published in the British Journal of Clinical Pharmacology has analysed the effect of consuming p-synephrine on the burning of body fat during exercise.

P-synephrine is an alkaloid found in a wide variety of citrus fruits such as oranges, mandarins, and grapefruits. Because of its chemical similarities to ephedrine, a nervous system stimulant, it has become a popular food supplement and is included in many weight loss products despite very little existing research that proves its effectiveness.

This study determined to examine the effects of p-synephrine on energy metabolism and the rate of fat and carbohydrate oxidation during rest and exercise. In a randomised, placebo-controlled, double-blind, experimental study, 18 subjects underwent two experimental trials. The first group consumed a dose of p-synephrine, whilst a control group took a placebo. An hour after ingesting the substance, energy expenditure and arterial tension were measured before and after physical activity on a static bike.

It was found that acute p-synephrine ingestion had no effect on energy expenditure, heart rate, or arterial pressure. However, the p-synephrine did increase the rate of fat oxidation at low and moderate intensities.

So wait a minute. Weight loss pills do work a fat-burning miracle after all?

Not exactly. The data suggested that p-synephrine supplements could be useful to increase fat oxidation by 7 g (0.07kg) per hour of exercise. The maximum rate found for fat oxidation during exercise was 0.7 g/min. That would suggest that in a very best-case scenario, an individual could burn 42 g of fat after an hour of exercise at that level of intensity with p-synephrine. But that is really hauling your ass in a workout by their measure, and the data merely suggests that p-synephrine was behind that and not different individual differences in metabolism between the study’s subjects.

The researchers themselves remained convinced that there was no case for the substance increasing fat loss without exercise, especially not for more extreme weight loss goals. As one of the lead researchers commented:

“[This] should be the aim: to lose a kilo [of fat] per month. It’s less attention-catching than miracle diet slogans, but scientifically speaking, effective change would be at that rate. The rate of loss could increase with p-synephrine, but always [when] combining the substance with exercise.”1

The authors also highlighted the need for further study to determine the long term effects of p-synephrine in the future.

References:

1. Jorge Gutiérrez-Hellín y Juan Del Coso. ‘Acute p-synephrine ingestion increases fat oxidation rate during exercise’. British Journal of Clinical Pharmacology (2016).

Sam MacIntosh

About Sam MacIntosh

Sam MacIntosh is a writer, editor, and a British Weightlifting and Precision Nutrition certified coach.

Sam played football from her pre-teens through to university, briefly switching to rugby when she was 25. It was then that she was introduced to strength training and weightlifting by a teammate and began training in CrossFit in late 2013. Shortly after, Chet Morjaria of Strength Education took her on as a powerlifting athlete and coached her to first in her weight class at the 2014 Welsh Powerlifting Open. She now trains in Olympic weightlifting and is the head barbell coach at CrossFit Gain in Norwich, England.

Sam is passionate about empowering athletes to think independently and neutralising nutritional propaganda. She's a recovering perfectionist, and enjoys coffee, books, and cinnamon donuts. You can connect with her on Twitter and Instagram.

View All Articles

Recommended Articles

heavytireworkout
The Right Way to Lose Fat: How to Exercise
‘How To’ Is Pointless Without ‘Why’
personaltrainertooclose
Is Personal Training Too Personal?
fitnesshappiness
How Much Does Happiness Weigh?

Primary Sidebar

Latest Articles

20 Best Home Gym Equipment Essentials for Cardio, Strength Training, and More

Hunter Labrada Looks Shredded Before Taking on 2023 Texas Pro and 2023 Tampa Pro

Lat Pulldown vs. Pull-Up: The Battle for a Bigger Back

2023 Strongest Man in Iceland Results — Kristján Jón Haraldsson Repeats

Latest Reviews

Breaking Muscle Best Protein Powder

17 Best Protein Powders for Weight Loss, Muscle Gain, and More

Athletic Greens AG1

Athletic Greens AG1 Review: Is This Greens Powder Worth It?

Best Adjustable Dumbbells

9 Best Adjustable Dumbbells for Home Gyms of 2023

Best Creatine

11 Best Creatine Supplements For Building Muscle, Cutting, and More

woman lifting barbell

Be the smartest person in your gym

The Breaking Muscle newsletter is everything you need to know about strength in a 3 minute read.

I WANT IN!

Breaking Muscle is the fitness world’s preeminent destination for timely, high-quality information on exercise, fitness, health, and nutrition. Our audience encompasses the entire spectrum of the fitness community: consumers, aficionados, fitness professionals, and business owners. We seek to inform, educate and advocate for this community.

  • Reviews
  • Healthy Eating
  • Workouts
  • Fitness
  • News

Follow Us

  • Facebook
  • Twitter
  • Instagram
  • Pinterest
  • RSS Feed

© 2023 · Breaking Muscle · Terms of Use · Privacy Policy · Affiliate Disclaimer · Accessibility · About