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Caffeine Consumption Stiffness


Hello guys,

I am experiencing stiffness in my legs lately after I use caffeine. It feels like my calves are shortening and my hip muscles are so stiff I cant even exorotate them normally without pain. I have read about caffeine and I found something about higher muscle contraction through more calcium release in the muscle. I want to keep using caffeine because it stimulates my nervous system very well and I didnt have these stiffness problems in the past when I also used caffeine. So I need a clue about what to change or what to do in order to keep using caffeine (pre-workout) without the stiffness. Most of my friends dont experience the same problem when taking the same pre-workout. What could be the problem? I am currently thinking about exhaustion of a certain mineral/vitamin that is used when you take caffeine but I am not sure about this theory. Below is the literature I have used.

Thank you for helping me out.

Mr. Smit (medicine student)

Abstract: The aim of this study was to investigate the effect of caffeine on the amplitude and rate of skeletal
muscle contraction using frog sciatic nerve-gastrocnemius muscle model. Caffeine is a xanthine alkaloid whose
use is widely unregulated. It is taken as a central nervous system stimulant in various foods and drinks. The
effect of caffeine on skeletal muscle contraction and a possible elucidation of its mechanism of action were
investigated. The sciatic nerve-gastrocnemius muscle preparation of the frog mounted on a kymograph was
utilized. Varying doses of caffeine was added to the organ bath at 5, 10, 15, 20 and 25 mg/mL and its effect on
skeletal muscle contraction was studied. The effects of caffeine preceded by administration of acetylcholine,
atropine, nifedipine, magnesium chloride and calcium gluconate at 25 mg/mL were also studied. A dose
dependent increase in skeletal muscle contraction (25.25±0.48, 49.00 ±1.23, 52.38±2.58, 59.25±1.11 and
68.50±0.87 mV; p<0.05) was observed on administration of increasing doses (5, 10, 15, 20 and 25 mg/mL,
respectively) of caffeine respectively. While a significant reduction (0.90±0.04 mV) and increase (77.50±1.56
mV) in strength of contraction was observed on administration of nifedipine and calcium gluconate
respectively. Administration of magnesium chloride caused a significant decrease in the strength of contraction
(28.25±5.01) as compared to control. However, there was no significant difference in the contraction period
and relaxation period between the treatment groups. The findings imply that caffeine increases skeletal muscle
contraction and suggests it exerts the effect through increasing calcium ion release.

Authors: Kolawole Victor Olorunshola and L.N. Achie
Department of Human Physiology, Faculty of Medicine, Ahmadu Bello University,
Zaria, Nigeria


Also worthy of saying is that I have used a pre-workout drink for a year constantly and that I didnt experience any problems last year. In the off-season (3 months in the summer) I didnt use the pre-workout drink. After that I started using again and thats when the stiffness showed up.


Stiff calf and leg muscles are a sign of magnesium deficiency. Caffeine is a diruertic. Diuretics worsen magnesium/potassium deficiency. My guess is that this is exacerbating a magnesium deficiency. You can easily see if my assumption s correct with an epsom salt bath. 3 cups epsom salt... You can also try magnesium (glycinate or taurate are best IMO) supplement. Boron also increases Mg absorption. I'd recommend going off the caffeine while you add in the Mg. Another test you can do is take ~400-600 mg of magnesium with ~20 ounces water about a half hour before you take the caffeine. Then see if you notice a difference. If the epsom salt bath makes a difference but the oral supplement does not, then you may have a mag absorption issue: variations in amount of stomach acid, commonly reduced in older adults, Excessive use of alcohol, Crohn?s disease, celiac sprue, and any disorder of the digestive or intestinal function, Kidney disorder, Genetic magnesium absorption disorder, Stress, surgery, or other chronic disorders such as diabetes, chronic diarrhea and/or vomiting.


Thank you Bulletprooftiger for the reaction, I have ordered magnesium chloride to see if I will notice a difference. I will repost again when I have it and report my findings.

p.s. I dont exactly know why magnesium chloride differs from other magnesium forms. I read that this is a better form for sportsmen. Is there somebody who knows more about this form of appearance and its effect?


I read somewhere that too much caffeine can constrict blood flow. Not sure if it is true or not, but I keep my caffeine per-workout to no more then 250mg. I have not had any problems that you stated with this subject. My per-work has 250mg ( I can not tolerate much more ) of caffeine and I drink a mixture of BCAA's during my work out. After training I use MAG-10.


You're welcome Flashakablackmamba. Alternatively, it is possible that the cramps/tightness could be from potassium deficiency (I'm guessing it's both to some degree).

Either way, if you try to take the supplement right when you have the symptoms (when you are dehydrated), you COULD have zero positive result and at the worst a completely negative result. Here's why: Diuretics flush the magnesium/potassium like I said above, which effectively lowers the tissue level (muscle). As tissue level drops, it has to go somewhere so it would naturally wind up in the blood. This increased the blood volume, which can send a signal to your body to not absorb any more. If you further supplement at this time, blood concentration of the mineral is further increased. Instead of supplementing right away, when you notice the symptoms, take 3 large glasses of water to flush your system. Then take the magnesium supplement with a meal rich in potassium.

Also, sugar can throw off you mineral levels (especially fructose).

Good luck figuring this out.


Thank you again Bulletprooftiger and duke6j.

I am currently supplementing 300mg magnesium 30 minutes before 250mg caffeine intake. I take the caffeine before the workout and afterwards (2 hours later) I take again 300mg magnesium.

I have tried this for 3 days now and it seems to reduce the stiffness and the cramps too. It feels like my legs are not feeling heavy anymore. The problems are not completely gone but I do notice progression.

@Bulletprooftiger, I consider buying additional potassium, zinc and copper. Because the magnesium supplementation is working, I think that the problem was a depletion caused by caffeine indeed. So if the caffeine depleted my magnesium levels, it will probably have depleted my potassium and zinc levels too. I am not worrying about calcium and sodium levels because calcium can be made by the body itself (also think that my calcium will not be depleted easily because I drink milk) and it will make my muscles contract less and sodium is more often too much available than too less in a western diet.

So I will try to take the potassium and zinc also 30 minutes before the caffeine intake. Or would it be better to take the minerals before sleeping after dinner together with vitamin D? I take the caffeine always before 16:00h