Cathy Yeckel, MS, PhD, exercise physiologist and human metabolism research, is assistant clinical professor at Yale School of Public Health. Dr. Yeckel is an avid runner and a member of UCANís (creator of SuperStarch) medical advisory board. She can share why turning on the bodyís ability to burn fat stores is the key for long-lasting energy as well as the following misconceptions about carbs, energy and fat among women.
Myth #1: Women can never burn more fat than men.
False. What we know from exercise research is that women champion fat burning during exercise and can reach a higher intensity of exercise while still burning relatively more fat as fuel than can men (1).
Myth #2: The practice of carb-loading before a competition works well for men and women to improve performance.
False. While carb-loading (glycogen super-compensation) is effective for performance in men, its benefit for women is less convincing. Unlike in men, the practice carried out in women requires women to increase their total daily energy intake beyond normal (potential for weight gain) (3). Everyone benefits from having glycogen stores topped up, but women may not benefit from super-compensated stores.
Myth #3: Performing low-intensity exercise is how women burn the most fat.
False. Women who are exercise trained have higher fat burning than untrained women. These women can achieve a maximal fat burn at a higher intensity, close to their ventilatory threshold (the point that lactate begins to accumulate in the blood) (2). Women shouldnít lock themselves into low and slow exercise, just the opposite. Adding in moderate to high-intensity workouts will force muscle to become even better at burning fat!
Myth #4: Ingesting simple carbs before/during exercise is a great fueling strategy to keep blood sugar steady and performance high.
False. When women ingest a simple carbohydrate (sugar-based bars, gels, drinks) before or during exercise their fat-burning advantage is lost ó they will burn more carbohydrate just like men (4). Plus, performance isnít necessarily enhanced. The body is so consumed with clearing sugar from the bloodstream that it canít mobilize its own fat stores to produce high rates of fat burning energy. The natural fuel mix is compromised. Instead, the key to unlocking the bodyís ability to mobilize fat stores as energy, all while keeping blood sugar steady, is a new complex carb (food product) Ė UCANís SuperStarch. SuperStarch gives the body the opportunity to burn carbs AND fat for long-lasting, steady energy.
Myth #5: After exercise there is a continued fat burn for several hours.
False: This is true for men, but does not appear to be as strong in women. Women return to a resting metabolic rate faster than men, which decreases fat-burning rates (5). Striving for exercise at a higher intensity helps promote longer fat burning.
1. Cheneviere X, Borrani F, Sangsue D, Gojanovic B, Malatesta D (2011) Gender differences in whole-body fat oxidation kinetics during exercise. Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme 36: 88-95
2. Astorino T A, (2000) Is the ventilatory threshold coincident with maximal fat oxidation during submaximal exercise in women. J Sports Med Phys Fitness. Sep;40(3):209-16.
3. James AP1, Lorraine M, Cullen D, Goodman C, Dawson B, Palmer TN, Fournier PA. (2001) Muscle glycogen supercompensation: absence of gender-related difference Eur J Appl Physiol. Oct;85(6):533-8.
4. Wallis GA1, Dawson R, Achten J, Webber J, Jeukendrup AE. Metabolic response to carbohydrate ingestion during exercise in males and females (2005) Am J Physiol Endocrinol Metab. Apr;290(4):E708-15. Epub 2005 Nov 8
5. Henderson GC Seual dimorphism in the effects of exercise on metabolism of lipids to support resting metabolism Front Endocrinol (Lausanne). 2014 Oct 7;5:162.
6. Devries MC1, Hamadeh MJ, Phillips SM, Tarnopolsky MA. Menstrual cycle phase and sex influence muscle glycogen utilization and glucose turnover during moderate-intensity endurance exercise. Am J Physiol Regul Integr Comp Physiol. 2006 Oct;291(4):R1120-8. Epub 2006 May 11.
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