Masters and Johnson were pioneering researchers in the study of the human sexual response cycle. Their studies were very controversial at the time, but now they’re a key part of our understanding of this topic. One of their biggest discoveries was the sexual response cycle. Thanks to their research, we now know about all the different phases our bodies go through during sex.
But you also have to remember that everyone displays their sexual response in a different way. So some people might pant, while other people hardly make any sounds at all. Some people move their body around wildly, while other people only move around a little bit. In spite of all these differences, the body’s physiological response to sexual arousal is always the exact same.
The four phases of the sexual response cycle
The sexual response cycle theory says that people move through 4 phases during their sexual response. It goes in this order: (a) excitement, (b) plateau, (c) orgasm, and (d) resolution. This order never varies. You always start with excitement and end with resolution. Let’s dig deeper.
The sexual excitement phase
This is where the physiological changes start, and what those do is show that your body is responding to the sexual stimulation. The stimuli at the beginning of the cycle can be either physical or psychological. This phase’s main function is to get your body ready for intercourse.
There are many different physiological changes in women. Vaginal lubrication increases extremely fast thanks to the parasympathetic system. There’s a dilation of the lower part of the vagina, which makes it easier for a penis to enter. There’s also an increase in the size of the clitoris and breasts because of vasocongestion.
There are also some physiological changes for men. Vasocongestion and the sympathetic system lead to an erection in the penis, along with tightening the scrotum and lifting up the testicles. Men experience frequent rectal contractions during this phase too.
Both sexes do have some physiological changes in common. For example there’s sex flush, an increased heart rate, and an increased blood pressure.
The plateau phase
The plateau phase is the central part of the cycle, and it’s also the longest because your body tries to stay in this state as long as possible. It’s the phase where you’re engaging in sexual activity. Your body has higher levels of muscle contraction and vasocongestion during it, because of an increase in sexual tension (not the psychological kind). The point of this phase is to keep you in a sexual state until you reach climax, also known as orgasm.
Here are the physiological changes for women during this phase: contraction of the vaginal walls, clitoris retracted inward, increased uterus size, and a darkening of the outer labia. These changes are part of what Masters and Johnson called the formation of the orgasmic platform. Women will also start to have involuntary contractions in the rectum, just like men do during the excitement phase.
As far as men, their penis reaches its maximum level of erection and their testicles increase in size and go up as high as possible. Pre-ejaculatory fluid also build up in their sexual glands to clear the pathways of any semen residue. They keep on experiencing rectal contractions.
The physiological changes in common between the sexes are the same as the last phase. Heart rate, blood pressure, and respiratory rate keep going up.
The orgasm (or climax) phase
The orgasm phase involves an explosive discharge of neuromuscular tension. It’s extremely pleasurable. It happens suddenly and involuntarily when stimulation reaches its peak intensity. It also marks the end of sexual activity. From a psychological point of view, the pleasurable experience is like behavioral reinforcement.
With women, the orgasmic platform contracts every .8 seconds, about 5-12 times. They also have contractions in their sphincter and other muscle groups.
Men have contractions in their urethra and pelvic muscles. This makes it so that the penis can ejaculate and send out semen. The sympathetic system makes their ejaculation happen all the way down to the level of their nerves.
Both sexes continue with all the bodily increases from the earlier phases. In other words, heart rate, blood pressure, and respiratory rate all keep going up.
The resolution phase
This is when sexual tension goes down. Your body goes back to how it was before the excitement phase. It usually takes about 15-30 minutes to reverse all the processes from the earlier phases.
Men go into a “refractory period.” During this phase it’s really hard for them to get an erection and have an orgasm. There’s no specific amount of time it lasts, either. It could go for minutes or hours, and that number increases as you get older.
Women don’t have a refractory period. That means they can have multiple orgasms in a much shorter amount of time. But there’s another important thing that sets them apart from men. Men usually go through the cycles in a very similar way in terms of time and activation. Women, on the other hand, are much more diverse here. For example, some women make it to the orgasm phase extremely fast, while others get there much more slowly.