Friday, January 12, 2007

Hot sex for hard bones

Hi everyone,

Exposure to low frequency mechanical vibration for two to ten minutes per day stimulates musculoskeletal development (1, 2). The vibration used in both studies was 30 Hz. Before you rush out and buy a vibration machine consider that the natural frequency of orgasmic vibrations is 8 Hz. Which is of little value if you're the only one experiencing them. But, consider if you're with a partner. The phenomenon of resonance kicks in.

http://www.elitesoft.com/sci.hvac/itreson1.html explains what resonance is: "When the natural frequency of an object is excited by a vibration of the same frequency the objects natural frequency escalates to a point much greater than the exciting force or vibration. Hence, the singer breaks the glass, or the walls of Jerico come falling down."

So, hot sex will lead to resonance vibrations in both partners of 16 Hz, 32 Hz, etc. 32 Hz is close enough, I suspect, to help our bones and muscles.

Note that 32 Hz is 4 times 8 Hz which makes (3) interesting indeed. Research has shown that having mutual orgasms is four times as beneficial as doing it solo. The researcher seems to have a blind spot for gay sex since the two choices were heterosexual or solo. I'm sure gay sex together works just fine too although some of the men might have trouble making the two minute point. :)

6/13/2008 update - see (4) for a recent report on vibration and our health. The researchers note that vibration improves flexibility. No kidding!

11/27/2016 update - see (5) which discusses vibration and obesity control. It links to a study at (6) which mentions how this ties in with bone health.

1. J Bone Miner Res. 2006 Sep;21(9):1464-74
Low-level, high-frequency mechanical signals enhance musculoskeletal development of young women with low BMD....
The potential for brief periods of low-magnitude, high-frequency mechanical signals to enhance the musculoskeletal system was evaluated in young women with low BMD. Twelve months of this noninvasive signal, induced as whole body vibration for at least 2 minutes each day, increased bone and muscle mass in the axial skeleton and lower extremities compared with controls....CONCLUSIONS: Short bouts of extremely low-level mechanical signals, several orders of magnitude below that associated with vigorous exercise, increased bone and muscle mass in the weight-bearing skeleton of young adult females with low BMD. Should these musculoskeletal enhancements be preserved through adulthood, this intervention may prove to be a deterrent to osteoporosis in the elderly.
PMID: 16939405

2. J Sports Sci. 2007 Jan;25(1):111-9
Whole-body vibration can reduce calciuria induced by high protein intakes and may counteract bone resorption: A preliminary study....
Excess protein intake can adversely affect the bone via an increase in calcium excretion, while suitable mechanical loading promotes osteogenesis. We therefore investigated whether vibration exposure could alleviate the bone mineral losses associated with a metabolic acidosis. Ten healthy individuals aged 22 - 29 years (median = 25) underwent three 5-day study periods while monitoring their dietary intake. The study consisted of recording the participants' usual dietary intake for 5 consecutive days. Participants were then randomly divided into two groups, one of which received a protein supplement (2 g . kg-1 body mass . day-1; n = 5) and the other whole-body low-magnitude (3.5 g), low-frequency (30 Hz) mechanical vibration (WBV) delivered through a specially designed vibrating plate for 10 min each day (n = 5). ...results indicate that vibration stimulation can moderate the increase in bone resorption and reduction in bone formation caused by a metabolic acidosis.
PMID: 17127586

3. http://sexuality.about.com/od/sexualscience/a/weirdscience3.htm
Weird Sexual Science: Sex with a partner is 400% better
From Cory Silverberg,
Orgasm Study Offers Status Quo and Universal Generalizations
The same researcher who last month brought us the study suggesting that heterosexual intercourse was much better than any other kind of sexual behavior, is at it again.

This month New Scientist is reporting on a study by Prof. Stuart Brody (and colleague) that examined the blood level of the hormone prolactin following heterosexual intercourse versus masturbation. Prolactin is related to feelings of sexual release. The results?

After orgasm from sexual intercourse, the increase in blood prolactin levels was 400 per cent higher in both sexes compared with after orgasm from masturbation. The resulting headline (which I copied above) suggests that heterosexual sex is 400% better than masturbation. Prof. Brody is quoted as saying “this explains why orgasm from intercourse is more satisfying than masturbation.”

4. http://www.galenicom.com/es/medline/article/18477873/Whole+body+vibration+exercise:+training+and+benefits.
Whole body vibration exercise: training and benefits.
Autores:
Dennis G Dolny, G Francis Cisco Reyes
Idioma:
Eng.
Fecha:
14-05-2008
Revista:
Current sports medicine reports (1537-8918)
Entrega:
Curr Sports Med Rep. ;7(3):152-7
Abstract:
In recent years, it has been suggested that exercise using whole body vibration (WBV) platforms may increase muscle activity and subsequently enhance muscle performance in both acute and chronic conditions. WBV platforms produce frequencies ranging from 15-60 Hz and vertical displacements from ~1-11 mm, resulting in accelerations of ~2.2-5.1 g. Acute exposure to WBV has produced mixed results in terms of improving jump, sprint, and measures of muscle performance. With WBV training, younger fit subjects may not experience gains unless some type of external load is added to WBV exercise. However, sedentary and elderly individuals have demonstrated significant gains in most measures of muscle performance, similar with comparable traditional resistance exercise training programs. WBV training also has demonstrated gains in flexibility in younger athletic populations and gains or maintenance in bone mineral density in postmenopausal women. These promising results await further research to establish preferred WBV training parameters.
Copyright:
Current sports medicine reportsDepartment HPERD, University of Idaho, College of Education, Human Performance Laboratory, Moscow, ID 83844, USA. ddolny@uidaho.edu

5. https://theconversation.com/why-so-many-people-regain-weight-after-dieting-65095
Anyone who has tried to lose weight and keep it off knows how difficult the task can be. It seems like it should be simple: Just exercise to burn more calories and reduce your calorie intake. But many studies have shown that this simple strategy doesn’t work very well for the vast majority of people.

A dramatic example of the challenges of maintaining weight loss comes from a recent National Institutes of Health study. The researchers followed 14 contestants who had participated in the “World’s Biggest Loser” reality show. During the 30 weeks of the show, the contestants lost an average of over 125 pounds per person. But in the six years after the show, all but one gained back most of their lost weight, despite continuing to diet and exercise.

Why is it so hard to lose weight and keep it off? Weight loss often leads to declines in our resting metabolic rate – how many calories we burn at rest, which makes it hard to keep the weight off. So why does weight loss make resting metabolism go down, and is there a way to maintain a normal resting metabolic rate after weight loss? As someone who studies musculo-skeletal physiology, I will try to answer these questions.

Activating muscles deep in the leg that help keep blood and fluid moving through our bodies is essential to maintaining resting metabolic rate when we are sitting or standing quietly. The function of these muscles, called soleus muscles, is a major research focus for us in the Clinical Science and Engineering Research Center at Binghamton University. Commonly called “secondary hearts,” these muscles pump blood back to our heart, allowing us to maintain our normal rate of metabolic activity during sedentary activities.
Resting metabolism and weight maintenance...

6. http://ajpregu.physiology.org/content/288/3/R623.long
Am J Physiol Regul Integr Comp Physiol. 2005 Mar;288(3):R623-9.
DOI: 10.1152/ajpregu.00513.2004
Plantar vibration improves leg fluid flow in perimenopausal women.
Stewart JM1, Karman C, Montgomery LD, McLeod KJ.
Abstract
Recent studies have indicated that plantar-based vibration may be an effective approach for the prevention and treatment of osteoporosis. We addressed the hypothesis of whether the plantar vibration operated by way of the skeletal muscle pump, resulting in enhanced blood and fluid flow to the lower body. We combined plantar stimulation with upright tilt table testing in 18 women aged 46-63 yr. We used strain-gauge plethysmography to measure calf blood flow, venous capacitance, and the microvascular filtration relation, as well as impedance plethysmography to examine changes in leg, splanchnic, and thoracic blood flow while supine at a 35 degrees upright tilt. A vibrating platform was placed on the footboard of a tilt table, and measurements were made at 0, 15, and 45 Hz with an amplitude of 0.2 g point to point, presented in random order. Impedance-measured supine blood flows were significantly (P = 0.05) increased in the calf (30%), pelvic (26%), and thoracic regions (20%) by plantar vibration at 45 Hz. Moreover, the 25-35% decreases in calf and pelvic blood flows associated with upright tilt were reversed by plantar vibration, and the decrease in thoracic blood flow was significantly attenuated. Strain-gauge measurements showed an attenuation of upright calf blood flow. In addition, the microvascular filtration relation was shifted with vibration, producing a pronounced increase in the threshold for edema, P(i), due to enhanced lymphatic flow. Supine values for P(i) increased from 24 +/- 2 mmHg at 0 Hz to 27 +/- 3 mmHg at 15 Hz, and finally to 31 +/- 2 mmHg at 45 Hz (P < 0.01). Upright values for P(i) increased from 25 +/- 3 mmHg at 0 Hz, to 28 +/- 4 mmHg at 15 Hz, and finally to 35 +/- 4 mmHg at 45 Hz. The results suggest that plantar vibration serves to significantly enhance peripheral and systemic blood flow, peripheral lymphatic flow, and venous drainage, which may account for the apparent ability of such stimuli to influence bone mass.
PMID: 15472009

Nerissa

3 comments:

ShannonVyff(We_live_to_love:) ) said...

Yet another awesome, well put together post--we'll miss you at the CR society..

Shannon Vyff

Amy said...

So how are things? As with the others, I miss you over at the CR lists - I figured you'd be a prolific blogger, but you're letting me down :-). I hope things are ok and all your activities (work, school, etc.) are going ok. Bye for now . . .

Amy

Amy said...

So are you ok? I'm just a bit concerned that you've dropped off the map entirely. I'm not logged into my e-mail right now, but I'll send you a line that way, as well.

Hope things are ok . . .