Cortisol and
testosterone dynamics following exhaustive endurance exercise

T., Lane, A.R., & Hackney, A.C. (2016). European
Journal of Applied Physiology, 116(8)
, 1503-1509.

Take Home Message:
Following high-intensity endurance exercise, recovery may require 48-72 hours
for cortisol and testosterone to return back to resting levels.

running produces physiological stress to the body, resulting in neuroendocrine
(hormonal) responses. Specifically, cortisol (a hormone that is released in
response to stress on the body and can break down muscle tissue), increases and
testosterone (a hormone that builds up muscles tissue), decreases following
intense exercise. Due to this shift, the body is breaking tissue down more than
it is laying down, which may negatively affect recovery status; however,
research has only been conducted to assess the acute stage and the longer
lasting effects of the hormonal imbalance during recovery has not been
established. The long-term hormone responses are important to monitor in order to
prevent and detect overtraining in athletes. Therefore, the authors evaluated
12 elite male runners following a bout of exhaustive exercise (~
97 min) to assess cortisol and testosterone levels and
the effect to their recovery status. Baseline maximum oxygen consumption and
ventilator threshold were measured to determine appropriate training intensity.
Seven days later, athletes returned to the lab for the completion of the exhaustive
exercise session. The athletes rested in a supine position for 30 minutes
before providing their resting blood sample. The athletes were fitted with a
heart rate monitor, and allowed to warm-up prior to beginning the exhaustive
run (100% of ventilator threshold) on the treadmill until fatigue.  Following a five-minute cool down,
post-exercise blood samples were collected. The athletes reported back to the
lab at the same time of day 24, 48, and 72 hours after the endurance exercise
session, where blood samples were drawn again. Hormonal concentrations of
cortisol and free testosterone were assessed in all samples. Analysis revealed
a significant decrease in free testosterone that persisted up to 48 hours post-exhaustive
exercise before returning to baseline values at 72 hours. Furthermore, there
were significant increases in cortisol, which returned to baseline levels at 48
hours post-exhaustive exercise. There was a significant negative correlation
between cortisol and free testosterone levels immediately following the exhaustive

study attempted to provide an understanding of the effects of exhaustive
exercise on cortisol and testosterone concentrations during recovery. Findings suggest
that 48-72 hours of recovery may be required to return cortisol and
testosterone to resting levels. Understanding hormonal responses and the proper
recovery plays an essential role in athletic performance and preventing
overtraining. Athletes training at a high intensity may be compromising
muscular growth, power, and development, as well as overall sport performance,
if coaches do not allot sufficient recovery periods. Therefore, coaches and
health professionals may use cortisol and testosterone assessments to monitor
their athletes’ recovery status in order to install a training progression that
allows the athletes to have proper recovery time. It would be interesting to
observe whether similar hormonal patterns occur when athletes engage in resistance
training. While not all coaches may have the capability of drawing blood to
monitor these hormones, coaches may consider avoiding intense training on
consecutive days. Additionally, coaches may allow their athletes 48-72 hours to
recovery before completing another high-intensity exercise session. This would
enable athletes to perform at their full potential, while reducing possible
risk of overtraining.

Questions for
Discussion: How may these results change/remain the same if we look at resistance
training rather than endurance exercise? How could coaches modify their
athletes’ training if they observe low testosterone and high cortisol levels?

by: Jennifer Fields
by: Jane McDevitt


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Anderson, T., Lane, A., & Hackney, A. (2016). Cortisol and testosterone dynamics following exhaustive endurance exercise European Journal of Applied Physiology, 116 (8), 1503-1509 DOI: 10.1007/s00421-016-3406-y