Does playing chess burn as many calories as running?

Question

I heard once that when two Chess Grandmasters play a five hour game of chess, the intense concentration and focus they have causes their bodies to burn as many calories as someone playing a sport during that time, such as running.

For example, Dr. Robert Sapolsky claimed that:

… [with] chess masters in the middle of a tournament, they are going through six to seven thousand calories a day thinking. [They are] turning on a massive physiological stress response simply with thought and doing the same thing with their bodies as if they were some baboon that’s just ripped open the stomach of their worst rival — it’s all with thought.

Is there any truth behind this?

Running for that long would be the same as running a marathon, and I just don't believe that sitting playing chess can use as much energy. However I do believe that it must burn more calories then usual.

Answer 1

People have used chess as a model for studying stress responses and therefore have done a detailed metabolic analysis. The key data is in table 1 (p. 347); here it is, reformatted and converted to Calories/hr:

Energy expended (Cal/hr) Before      Beginning   Middle      End
------------------------ ----------- ----------- ----------- -----------
Mean                      91.8       100.2        91.8        93.0
Minimum                   68.4        70.8        70.2        68.4
Maximum                  120.0       132.0       120.6       122.4

These are comparable to light physical activity (desk work, etc.), and not even close to jogging (400-500 Calories/hr for someone weighing ~70 kg).

So, no, chess grandmasters do not come anywhere close to runners when it comes to caloric expenditure. Extremely stressful games could perhaps exceed even the maximum bounds here (the participants were competitive chess players, but not at the master/grandmaster level).

(Also, note that if chess grandmasters did burn that many calories, they would get at least as hot as runners do, and although you may seen top chess players mop their brow, you generally don't see them in light clothes sweating profusely even in cold weather.)

Answer 2

Mental effort does not significantly increase the amount of energy used by the brain.

source

the brain accounts for about 20% of the oxygen and, hence, calories consumed by the body. This high rate of metabolism is remarkably constant despite widely varying mental and motoric activity.

Average base metabolic rate for men is 1632 kcal per day, so the brain uses around 320 kcal per day.

Running uses around 100 kcal per mile, so running a few miles will use more energy than your brain does during an entire day.

Answer 3

It isn't directly related to the question although this study:

http://www.sciencedirect.com/science/article/pii/S030105110300156X

found that there are changes in physiology related to mental effort.

Abstract

Previous studies have operationalised mental effort via various indices of psychophysiology, particularly cardiovascular measures. Metabolic measures represent a complementary approach wherein mental effort investment is explicitly linked to the process of energy mobilisation. The purpose of this study was to contrast cardiovascular variables (heart rate, 0.1 Hz component of heart rate variability) with a metabolic measure (blood glucose) of mental effort. Twenty-nine participants were exposed to Stroop stimuli over a 45 min period under two conditions: (a) congruent (i.e. 100% congruent Stroop stimuli); and (b) incongruent (i.e. 100% incongruent Stroop stimuli). Performance, blood glucose, cardiovascular activity and subjective mood were measured. The results indicated that blood glucose levels were sensitive to both Stroop and time-on-task variables, whilst cardiovascular measures were only sensitive to the latter. There was also evidence of an association between blood glucose levels and response accuracy. The implications of these findings for the operationalisation of mental effort are discussed.