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Why You Need to Stop Weighing Yourself with Gary Slater

Feb 25, 2022

Why You Need to Stop Weighing Yourself with Gary Slater

Body composition is an aspect many triathletes really struggle with. At the end of the day, everyone wants to be leaner and faster, but changes without appropriate assessment and regular adjustments can often lead to performance detriments.


Here are some practicalities around how to manipulate your body composition as a triathlete, how to decide whether it’s useful, and how to accurately measure it.

Do changes in body composition just mean weight loss?

  • No! This should be a fat loss journey as opposed to a weight-loss journey
  • There are many tools you can use to assess body composition - all are not created equal
  • Weight loss does not always equal performance enhancement
    • Having a reduced energy availability can compromise fuelling and recovery
      • Quality of training will decline, leading to sub-optimal training adaptations
    • It can increase the risk of losing lean tissue/muscle mass
    • It can change the way individuals perceive themselves

What components are important when looking at body composition?

  • It’s important to consider both changes in fat mass and skeletal muscle mass

Why shouldn't you use the scales as an accurate measurement?

  • Your weight can fluctuate dramatically based on several factors - i.e. 'Noise Variables'
    • Hydration status
    • Hormonal changes
    • How much bulk you have in your stool
    • How much fibre you've recently had
    • If you've recently carb-loaded
    • How much you've eaten that day
  • Not seeing changes on the scales can make you feel disheartened, even though this is not indicative of your actual change in body composition

Well, should I use the scales at all?

  • It can still be a useful reference point
  • Limit your weigh in to a couple of times a week
    • It is important to get the average to account for the variability

When is the best time to weigh myself?

  • Weigh yourself first thing in the morning (i.e. fasted)
    • Empty your bladder
      • Check and see how hydrated you are based on urine colour
    • Have minimal clothing on

How can I track changes in body composition?

What is a DEXA Scan?

  • It was primarily used to assess bone health
    • It can provide information on your bone mineral density and overall bone health
  • It is also useful at tracking body composition change
    • Can provide an absolute measure of fat mass and lean mass
    • It can provide regional composition i.e. bone mineral density on left arm vs right
      • This may provide valuable information for athletes returning from injury
    • There is a small amount of radiation exposure, so typically you are limited to using it about 4 times a year
      • You’re only getting data every 12 weeks which may not provide enough information to adapt, and optimise your personalised plan
    • The data can be influenced by many factors, such as food and fluid
      • Therefore it is important to get a DEXA scan from a group who can provide you with guidance on how to generate the most accurate results
        • If you are interested, Taryn can provide details for quality DEXA scan services

What are Skin Folds?

  • This won't provide you with an absolute measure of your composition, nor fat mass and lean mass - however the changes assessed using this method can help determine whether the weight loss is coming off primarily as fat, or a combination of other tissues
  • This data can be consistently collected (versus a DEXA)
    • This can provide your Sports Dietitian with up to date assessments, allowing for continual changes to be made to your personalised program
  • It is important these are performed by a skilled Sports Dietitian, or someone with appropriate qualifications and training e.g. ISAK (International Society for the Advancement of Kinanthropometry) accredited
    • This can easily be done inaccurately if not done by a professional!

How do Skin Folds work?

  • They are implemented using a "very expensive set of barbeque tongs" that have a dial on them, used to assess the thickness of a compressed double fold of skin
  • This is assessed across seven sites of the body; some on the lower body and some on the upper body
    • This is important as individuals store fat in different areas of the body
      • Males typically store more fat around the central part of their body through the torso
      • Females primarily store fat on the lower parts of their body
    • Across the seven sites, a sum of those values are collected and is used to track change longitudinally
  • There are very little 'noise variables'
    • Not influenced by exercise or food and fluid intake so give a more accurate reading

Why is it important to have a Sports Dietitian to help me with my body composition goals?

  • Sports Dietitians are qualified at using skin folds
  • They have the skills to set up a meal plan to support individuals through their weight loss journey
    • This will be adjusted accurately over time due to changes in training, metabolic adaptations etc.
    • This will be periodised, providing you with sufficient energy tailored towards your varied energy requirements and training days (you can’t eat the same, seven days of the week!)
  • Based off the data collected, they can make informed decisions as to whether or not a body composition change is actually beneficial
  • They can help mitigate any potential negative implications of a weight loss journey


To go deeper, listen to the Triathlon Nutrition Podcast Episode 29: Why You Need to Stop Weighing Yourself with Gary Slater


If you’re interested in joining the Triathlon Nutrition Academy, pop your name on the waitlist NOW | Join the TNA Waitlist

If you are looking for a Sports Dietitian and want to learn more about working with me, click HERE to see what I offer for private, 1 on 1 consultation.



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