I'm sorry but high protein low carb will only ever work if you are also HIGH FAT. You probably are super low on calories and your metabolism has likely slowed to that of a pre-teen female's. You should read some stuff about leptin and thyroid regulation as a response to various macronutrients and overall caloric intake.
I don't know what your riding and Army training are like, but I'm guessing you do a lot of cardiovascular activity. Fuel it. Drop the protein down. Endurance athletes generally require less than pure strength/power athletes. Lyle McDonald has some great free articles on his site www.bodyrecomposition.com
. Read as many as you can specifically his articles on CHO and protein requirements. My guess is you are probably hovering around 40%-50% of your diet (or more) from protein, and maybe 25% from the other two macros at most. Normally, and percentages are not always the most accurate way to break down a diet, an endurance athlete would require around 50%-60% of their diet to be from CHO at the very least. Right now its trendy to avoid processed carbs, which definitely aren't the best, but starchy vegetables, rice, and numerous legumes also have a very high protein and trace nutrient content as well and are perfectly acceptable energy sources.
To give you an idea of my daily intake on a maintenance day:
6 feet 2 inches tall, 28 years old
On a recovery spin or off day: 2400-2600 calories (Using BW in lbs x 15-16). I shoot for 4-5g/kg of CHO, 1.25g/kg of protein, and do try to keep fat on the lower side and it ends up fine. This ends up somewhere around 290-360g of CHO, 90-100g of protein, and fat whatever it ends up at.
Ride days really differ depending on what I did the previous day, that day, the next day, and the next block so I can't really advise you there. I've struggled with trying to maintain weight in the past and tried about every type of diet imaginable and restricting my CHO intake was probably the most detrimental thing I have done in terms of performance and maintaining a healthy metabolism.
No supplement will build muscle. You guys are talking out of your assholes. Creatine does not actually build muscle, it helps to synthesize ATP faster for very short duration activity. It would do nothing for a cyclist, but would help a strength athlete spending less than 12 seconds under tension.
Protein does not also necessarily build muscle. It can prevent catabolism, maintain a positive nitrogen balance, and promote anabolism, but there is nothing about whey protein that makes your body say "Oh damn, better go make a ton of muscle". Muscle gain is determined by genetics, diet, and type of exercise in that order. I've yet to see a single endurance athlete accidentally gain too much muscle by riding a bike although many gain plenty of fat and get dad legs and think that they've gained muscle.
Don't take me too seriously. The only person that doesn't hate