Muscle growth is more difficult to achieve in older adults than younger adults because of biological aging, which leads to many metabolic changes detrimental to muscle growth; for instance, by diminishing growth hormone and testosterone levels. Some recent clinical studies have shown that low-dose HGH treatment for adults with HGH deficiency changes the body composition by increasing muscle mass, decreasing fat mass, increasing bone density and muscle strength, improves cardiovascular parameters, and affects the quality of life without significant side effects.[45][46][unreliable medical source?][47]
(1) Water - I drink this all the time. Mainly in the morning. Doesn’t it make sense to hydrate upon waking up? I use to get nauseous, but that was because of a poor “diet”/food choices. Now, it’s like a filtering fluid at this time of day (morning). I drink it all day, but I have like 1 water bottle every hour. It’s easy to remember and to do (well, for me). We should aim for around 100oz of water, consuming all this in one time would suck. So “timing” water (which is a nutrient) is considered “nutrient timing”.
In addition to adequate protein, you need more calories (your protein intake contributes to your total caloric intake, so these two go hand in hand). Use the following formula to calculate the number you need to take in daily to gain one pound a week, and break down your diet using the macro guidelines listed above. (Give yourself two weeks for results to show up on the scale. If you haven't gained by then, increase your calories by 500 a day.)
(4) Insulin is a fat storage hormone - this isn’t true, okay kinda. Like I mentioned, both insulin and protein trigger insulin. If insulin was the issue than high protein intakes should has a worse reputation beyond what it currently has. Insulin has a job of transporting nutrients into cells. Carbs have a more direct connection to insulin than protein, so when carbs are consumed, insulin is spiked higher. Insulin will take the carbs (sugars) and transport them into cells for energy and then the rest into glycogen to save for later. If glycogen is full, then insulin still has a job to do. It doesn’t just float around dumb founded. It takes the carbs (sugars) and stores then into fat. It’s smart like that. But, we abuse that system by eating too many carbs and being in a surplus. The body doesn’t want to convert carbs into fat, that’s what fats are for, yet we abuse and do it anyways.
Rest your hip. Sore hip flexor muscles can benefit from rest. Avoid the activities that caused your pain. Ice your affected hip for 20 minutes at a time, several times a day. Keep the leg of your affected hip elevated as much as possible 48 hours from the first onset of pain. You can also take over-the-counter pain medications to help control pain.
Another common reason I see glutes that aren’t working properly is due to injury. Often an injury happens that changes the mechanics and motor programming of a person’s body. This can lead to some muscle groups becoming overactive, while others become underactive (think: compensation). This can alter things for a long time without the person even knowing it. 
Keto is for everyone. This has to do with fats. If someone has a high body fat percent, why would they do Keto? They already have enough fat to rely on. Someone with low body fat would benefit from constant fat as they don’t have enough stored fat to provide energy when needed. People with high body fat already contain the source of energy required for moments needed. People with low body fat have to outsource this energy through food with fats.
How to do it: Lie on your back with both feet planted firmly against the flat base of a Bosu ball, knees bent. Stabilize your body. If you’re feeling a bit wobbly, your arms can hover on either side of you in case you fall in one direction. If you feel balanced, raise your arms straight up above your chest, hands clasped to challenge and work your stability. Drive your hips toward the ceiling, then lower and repeat.