Posts Tagged ‘testosterone’

Improve your Fat Loss – Sleep Habits Can Hinder or Improve Progress

          Are you continuing to run off of only 5 hours of sleep and hoping to improve body composition? If this is you, unfortunately you are high-jacking your progress and likely regressing. The human body’s metabolic processes are largely influenced by the hormones of the endocrine system which cycle throughout 24 hours. Two hormones worth noting are Cortisol, which increases in times of stress and is associated with decreased performance and Testosterone, which promotes muscle growth (which burns calories) and increases metabolic rate (yes women have testosterone too) . Other hormones affected by sleep include Leptin and Ghrelin which have roles in hunger suppression and meal initiation respectively. In short, if sleep is of poor quality or quantity these hormone cycles are disrupted and even inverted. Research shows that both proper sleep quantity and quality can contribute to a successful weight loss program. One study associate higher success rates of 33% for weight loss programs in middle aged overweight and obese women for those women who slept more than 7hr and had good subjective quality of sleep.

Tips for Improving Sleep Quality/Quantity:

-Sleep in a room that is completely dark

-Avoid caffeine,  nicotine, sugar after lunch

-Drink water

-Keep your sleeping routine consistent

-Decrease exposure to TV or computer several hours before bed

-Shoot for 7-8 hrs of sleep


Article written by Rec. Sports & Fitness Center (MSU) certified personal trainer – Kevin Erickson.


Chaput JPTremblay A. Obesity Facts. 2012;5(4):561-6. Sleeping habits predict the magnitude of fat loss in adults exposed to moderate caloric  restriction. doi: 10.1159/000342054.

Chek P. (2012)  How to eat, move, and be healthy: Your personalized guide to looking and feeling great from the inside out San Diego:C.H.E.K. Institute

Thomson CAMorrow KLFlatt SWWertheim BCPerfect MMRavia JJ… Rock CL. Obesity (Silver Spring). 2012 Jul;20(7):1419-25. Relationship

between sleep quality and quantity and weight loss in women participating in a weight-loss intervention trial. doi: 10.1038/oby.2012.62.

Neuroendocrine Response to Resistance Training

What is the neuroendocrine response, and how do I get it?

Neuroendocrine refers to interactions between the nervous system and the endocrine system. So what does this have to do with fitness? Muscle growth and strength increases largely depend on the neuroendocrine adaptations and acute responses evoked during exercise. Some helpful hormones that are released include testosterone, GH or growth hormone, cortisol, insulin-like growth factors (IGF-1), insulin, and the catecholamines. All of which play a role in the process of muscle breakdown and rebuilding. The breakdown, or catabolism, happens during exercise and the rebuilding, or anabolism, occurs during recovery.

Certain exercises and manipulations of exercise protocols can maximize the neuroendocrine response. The most effective exercises that stimulate the neuroendocrine system include large groups of muscle. Kraemer et al. found that “Large muscle-mass exercises such as the Olympic lifts, deadlifts and jump squats have been shown to produce large elevations in testosterone in comparison with small muscle-mass exercises” (2005). These types of exercises when done prior to smaller exercises significantly increase the amount of testosterone circulating in the blood a short time after exercise while exercises such as “bicep curls” done without doing lower body large muscle mass exercises beforehand did not (Hansen et. al. 2001).

Now let’s focus in on testosterone. Not only does the type of exercise matter but also how that exercise is performed is essential to eliciting a significant neuroendocrine increase of testosterone concentration. The intensity, volume, and rest interval of the exercise being the major factors in programming; the intensity of exercise is how hard it is or the amount of resistance. The volume changes with the number of sets and repetitions performed Volume= (Sets x Reps x Resistance). The ideal programming for a good acute testosterone response according to Kraemer et al 2005 is a high volume with moderate to high resistance. Other factors that influence this acute response include age, sex, and training status.

One of Kraemer’s programs showed significant acute increases of testosterone and involved 8 exercises total with 3-5 sets done with 5 repetitions with 1 and 3 minute rest intervals (1991). Another significant change was recorded by Pakarinen with a program of 10 sets of 10 repetitions at 70% of 1 Repetition Maximum (1993). These are but a few ways of programming effectively for muscle growth and strength.

To put it in simple terms in order to maximize neuroendocrine response focus on working large muscle groups before smaller muscle groups. Use higher volume and moderate to high intensity with shorter rest intervals between sets.



Hakkinen K. Pakarinen A. Acute hormonal responses to two different fatiguing heavy-resistance protocols in male athletes. J Appl Physiol 1993;74:882-7

Kraemer W.J., Gordon SE, Fleck SJ. Et al. Endogenous anabolic hormonal and growth factor responses to heavy resistance exercisein males and females. Int J Sports Med 1991; 12:228-35

Kraemer W.J., Ratamess N.A. Hormonal Responses and Adaptations to Resistance Exercise and Training. Sports Medicine 2005;35(4)

This article was written by Kevin Erickson ACSM-HFS.  Kevin is currently accepting new clients at the Marga Hosaeus Fitness Center.  Call 994-6309 for more information about Kevin’s training methods.

Testosterone and Strength Training in Women

Most women choose to neglect strength training due to the “bulk” factor. It is believed by some that lifting weights will cause a women’s muscle mass to grow or bulk, and therefore create a masculine figure. This is clearly a misunderstanding. The female physique will remain essentially the same, although some minor curves may change. These minor changes are for the better:

-slimmer waistline                                                           -defined arms and shoulders

-lower percent body fat                                                 -defined thighs and legs

These changes are due to a body composition transformation rather than the misconception of “testosterone building bulkiness.” Testosterone is present in the female body; however, due to the lack of receptors and direct production site of the hormone adaptations to resistance exercise plays only a minor role.

Women hold a 15-20 fold LOWER concentration of testosterone than men do. WOW! There have been studies that have shown changes in testosterone levels during strength training and correlated with muscle force production characteristics; although no significant increases were observed.

IN MEN there appears to be a relative intensity and volume threshold which must be reached to induce a testosterone response. For instance, 3 sets of 6 repetitions at 100% of 6RM (rep maximum) and 5 sets of 10 repetitions at 10RM both induced a significant testosterone increase. However, 70% of the RMs for both of those did not induce an increase in testosterone. This happens due to the presence of Leydig cells which women do not have! Leydig cells are the primary production site of testosterone and are located in the male gonads. “The absence of functioning [Leydig] cells dedicated to testosterone production and release prevents large acute increases in circulating testosterone in females…in response to exercise” (Vingren Et al 1039).

In conclusion, women should not fear strength and resistance training. Men hold the testosterone levels capable of creating a prominent response to resistance exercises, but women do not. So women get your lift on and confidently slim down!


National Strength and Conditioning Association. Essientials of Strength Training and Conditioning. Edited by Baechle, Thomas R., Earle, Roger W. (2008). Pages 49-56.

Vingren et al. (2010). Testosterone Physiology in Resistance Exercise and Training. Sports Med 2010: 40 (12) 1037-1053.

Article written by Michelle Knurr.  Michelle is available for personal training sessions at the Hosaeus Fitness Center located at Montana State University-Bozeman.  Contact Michelle today for more information!