If you trainer gave you these supplements, that gives you reason to be skeptical (even suspicious) about his knowledge of the body, its mechanisms, and diet & nutrition.
Let's go over a couple of his recommendations:
- Vitamin C 3000mg per day - Recommended daily intake of vitamin C is about 90mg for an adult male but many athletes can require upwards of 100mg per day. (Ultra endurance athletes may require as much as 500mg per day- marathon runners and the like). Since vitamin C is water soluble, any more than what your body uses is urinated out. AND since many juices and foods in our diets contain vitamin C, you may be getting more like 3500 mg per day. Essentially all your trainer is doing is giving you expensive urine, and REALLY stressing your kidneys, since the kidneys have to filter all this out. High doses of vitamin C supplementation have been linked to kidney stones, and Mayo Clinic recommends not exceeding 2000mg as an upper limit. (http://www.health.harvard.edu/blog/high-dose-vitamin-c-linked-to-kidney-stones-in-men-201302055854, http://www.mayoclinic.org/drugs-supplements/vitamin-c/dosing/hrb-20060322)
- Cinnamon Extract- Supplementation of cinnamon extract has been shown to help blood glucose levels in DIABETICS, however, (much like above) the dose your trainer is giving you is absurd. In "Cinnamon extract improves fasting blood glucose and glycosylated hemoglobin level in Chinese patients with type 2 diabetes., by Lu T1, Sheng H, Wu J, Cheng Y, Zhu J, Chen Y." subjects were given 360mg per day as a maximum dose. Let's assume cinnamon extract DOES help non-diabetics as well. If so, a small dose might not be a bad thing. However, 2000mg per day is bad news- most cinnamon extracts have coumarin (which gives it the strong flavor), and coumarin has been shown to have negative effects on both kidney and liver function.
- Glutamine, BCAA's, Arginine, and individual Amino Acids - Your body creates muscle by taking protein (amino acids) and using it to help satellite cells fuse to muscle fibers. Since you need all amino acids to make muscle, taking one or two amino acids, or just BCAA's will do little to nothing to build muscle- but again, and this is why I have been critical of your trainer, all this extra protein and amino acid will have to be filtered by the kidneys. bad bad bad.
- Multivitamin - Same reasons as above (kidney stress, unnecessary levels/doses, you probably get most of it from your diet anyway...)
Unfortunately, there are no real requirements to be a trainer (most can simply pay $100, take a test and then dispense whatever bad information they want to people who will listen). It is an unfortunate part of the business but it is a reality, like trying to be a race car instructor after taking your 16 year old driver's test.
Ultimately, if you are eating a good diet of about 60% carbohydrates, 20% protein, 20% fat (and avoiding trans-fats, saturated fats, etc) your diet will cover all of your nutritional needs.
If you are sitting all day except for the gym, try adding some more exercise to your day (walking before or to work, climbing stairs instead of elevators, etc).