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How to Fuel and Hydrate your Training and Racing | #20 ft. Lexi Kelson RD, M.Sc.

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In this episode, I interview Lexi Kelson, an entrepreneur and registered dietitian, about the importance of hydration and proper fueling for endurance sports. We discuss her background and how she got involved in the field of sports performance and nutrition. Lexi explains the process of guiding athletes in developing personalized fueling and hydration plans, emphasizing an individualized approach based on an athlete's gut tolerance and specific needs. We highlight the significance of practicality in achieving optimal performance and the importance of avoiding race day changes to prevent gastrointestinal issues. We discuss various aspects of fueling and hydration for endurance events. We cover topics such as training in hot conditions, sodium and sweat rates, fluid retention and the menstrual cycle, adjusting fluid intake, the risk of intaking too much sodium, underdoing vs overdoing sodium intake, adjusting sodium concentration, fluid intake and sweat sodium concentration, and fluid testing and adjusting concentration.


1) Individualized fueling and hydration plans are crucial for optimizing performance in endurance sports.

2) Building gut tolerance through gradual increases in carbohydrate intake can help athletes reach higher levels of fueling.

3) Practicality should be prioritized in fueling and hydration strategies to ensure adherence and comfort during training and racing.

4) Avoiding race day changes to fueling and hydration plans can help prevent gastrointestinal issues and improve performance.

5) Training in hot conditions can impact your stomach's ability to handle fuel, so it's important to train your gut in hotter conditions.

6) Sweat sodium concentration can vary for women based on their menstrual cycle, so it's important to be aware of potential changes in fluid retention.


If you have a question or topic you want us to address, leave a comment!

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00:00 Introduction and Background

01:24 Importance of Hydration and Sweat Testing

03:14 Lexi's Journey to Endurance Sport and Precision Fuel and Hydration 08:28 Transitioning to Nutrition and Sports Performance

12:21 Phil's Journey to Physiology and Sports Performance

16:15 Following Your Passions and Creating Your Own Career

20:40 Guiding Athletes in Fueling and Hydration

25:22 Individualized Approach to Fueling and Hydration

29:52 Practicality and Optimal Performance

33:44 Building Gut Tolerance and Avoiding Race Day Changes

34:16 Training in Hot Conditions

34:59 Sodium and Sweat Rates

35:58 Fluid Retention and Menstrual Cycle

37:44 Adjusting Fluid Intake

38:12 Risk of Intaking Too Much Sodium

39:19 Underdoing vs Overdoing Sodium Intake

40:53 Adjusting Sodium Concentration

42:00 Fluid Intake and Sweat Sodium Concentration

43:40 Fluid Testing and Adjusting Concentration

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