How many calories does one need during a day?
Uh…doesn’t the FDA recommend 2000 calories? Yes, that’s a commonly bandied about number, but if it were true we all should were the same size shoes and pants! Obviously, our requirements depend heavily upon our age, height, weight, lifestyles, gender and Body Mass Index (BMI).
The table below shows the Estimated Energy Requirements for an “average” person with a BMI of 21.5 for females and 22.5 for males [Source: Institute of Medicine's Dietary Requirement Report (2002)]
If that’s not enough, we need to figure out a way to parse those “2000 calories” into carbohydrate, protein and fat. After all, 2000 calories of Krispy Kreme donuts a day is not going to do any good in the protein department.
A gram of carbohydrate generates 4 calories, so does a gram of protein. Fat being fat, has to win and thus generates 9 calories.
The max target for fat within the 2000 calorie diet is 65 g which is roughly 600 calories. At least 1200 calories (~300g) is to come from carbohydrate, which leaves about 200 calories (~50g) of protein a day. A thumb rule that many follow is 1g protein per Kg (2.205 pounds) of body weight per day.
What are the protein requirements for athletes?
For athletes, the increased caloric intake should be in the form of carbohydrate and protein. It is important to intake sufficient quantities of carbohydrate, which is the primary source of energy. Insufficient carbohydrate could have an adverse effect of utilizing too much of protein stored in lean muscle as an energy source.
In addition to expending energy (burning calories), strenuous physical activity consumes and damages muscle. Protein is required to rebuild and repair this muscle. Conservative estimates peg 6% of calories consumed during exercise to be replenished by protein.
For 1-1.5 hours of moderate activity this translates to 10-11 grams of protein which increases total requirement to about 1.2g per Kg of body weight. Research has shown that the requirements can be upto 1.6g for intense athletes (endurance or strength).
All of these proteins can be obtained from plant based sources. The body is agnostic to the source, as long as the sufficiency and balance requirements of amino acids (the building blocks of protein) are met.
More about amino acids and plant sources of protein in another post.
I weep for my Guyana. Cynthia @ Forgive Me My Nonsense.