Caffeine and Fitness
There's a lot of confusion surrounding how caffeinated drinks fit into a healthy diet. For most people, coffee is a great way to boost energy and performance with minimal side effects (I’m drinking coffee as I write this). However, for some people, caffeine may slow progress towards health and fitness goals.
The good: caffeine and athletic performance
I love coffee and drink a good amount - its low calorie (about 5 calories per cup of black coffee, so essentially it’s zero calorie), comes from a natural source, and boosts energy and athletic performance.
Athletic performance:
Caffeine is an ergogenic aid (a substance and boosts athletic performance). Once it’s in your system (within about 30-45 minutes after ingestion), it boosts performance by opening up airways and dilating blood vessels. As a result, the body can transport oxygen and energy to fuel exercise at a faster rate.
Studies have shown that low doses of caffeine lead not only to improved endurance athletic performance and strength performance (especially with upper body lifts).
What’s an effective dose of caffeine?
Studies conclude that about 3-6 mg per kg of bodyweight should be sufficient to boost performance.
I’ll use myself as an example:
Weight: 145 lb, or 65.9 kg (weight in lb/2.2)
This means that up to about 197-395 mg of caffeine could benefit my performance. Considering the average cup of coffee has 95 mg of caffeine, this means approximately 2-4 8oz cups of coffee could help aid my endurance and strength performance if incorporated into a pre training regimen.
The bad: caffeine and stress
Hormonal balance:
The most important, potentially negative side effect that I want to cover today is the effect that caffeine can have on hormonal balance and stress, especially in women. Cortisol is the main stress hormone that our bodies produce, and caffeine intake is associated with high, unregulated levels of the hormone. For some, caffeine exacerbates the biological effects of underlying stress in our daily lives.
Why does this matter for weight management and athletic performance? Outside of the mental and emotional effects of stress, these hormones also have a biological effect on weight management and performance. High cortisol levels are associated with an increased rate of fat storage, increased muscle protein breakdown (making it harder for you to build the muscle you work for during training sessions), and less control over cravings (neural receptors for hormones that are responsible for the feeling of fullness are blocked or inhibited when cortisol levels are high).
What you should do: Although caffeine does not always lead to high stress hormone levels, if you feel like you’re doing everything to work towards your fitness goals and still not seeing the progress you want, underlying stress might have a lot to do with it (especially for women, who are more sensitive to this hormonal balance). Experimenting with eliminating caffeine (and alcohol) may be something worth trying.
Two other considerations:
Sleep - Caffeine is also known to alter sleep schedules, making it harder to get to sleep on time and then interrupting sound sleep when you do get to sleep.
Digestion - Caffeine is pretty acidic and is known to cause mild indigestion. For most, caffeine provides an effective energy boost prior to a workout. However, if you've been finding that your stomach is upset during workouts it may be beneficial to try limiting coffee before workouts.
sources:
Effects of caffeine on time trial cycling performance:
https://www.ncbi.nlm.nih.gov/pubmed/19208924
The effect of caffeine as an ergogenic on anaerobic exercise
https://www.ncbi.nlm.nih.gov/pubmed/18708685
Could hormones be blocking your clients’ success?
https://www.acefitness.org/education-and-resources/professional/prosource/january-2016/5764/could-hormones-be-blocking-your-female-clients-success