Caffeine has impacts beyond motivation. It has been studied on the context of cyclists and boosts ability to ride. So does beet root.
Creatine has been studied to have other small effects too..
What too, the above have effects on muscle endurance, though for resistance training the effects may vary well be small. Further, this study took people that were not trained. 5lbs of muscle is a lot.. these folks might have gone from 50lbs to 55lbs, an extra 0.1lbs due to a supplement would be noise. I think this study needs muscle biopsies to measure creatine levels accurately to tease out those that are getting plenty from their diet vs not. Or.. try to have a large control group that gets zero creatine in their diet.
AFAIK creatine supplementation is something to think about after a year or two of training, for advanced intermediates.
Here are some sources with how caffeine and nitrates help at least endurance performance:
Creatine has been studied to have other small effects too..
What too, the above have effects on muscle endurance, though for resistance training the effects may vary well be small. Further, this study took people that were not trained. 5lbs of muscle is a lot.. these folks might have gone from 50lbs to 55lbs, an extra 0.1lbs due to a supplement would be noise. I think this study needs muscle biopsies to measure creatine levels accurately to tease out those that are getting plenty from their diet vs not. Or.. try to have a large control group that gets zero creatine in their diet.
AFAIK creatine supplementation is something to think about after a year or two of training, for advanced intermediates.
Here are some sources with how caffeine and nitrates help at least endurance performance:
https://www.cptips.com/nitrate.htm
https://www.cptips.com/caff.htm