The Limits of Human Endurance = Pregnancy!

What is the ultimate limit of human endurance? Is it mountaineering expeditions to the world’s highest peaks? Is it riding a bike across a continent? Running a marathon every day? No, no, and no. The single greatest feat of sustained human endurance is….. pregnancy. 

Yes, you read that correctly! A recent paper (https://advances.sciencemag.org/content/5/6/eaaw0341/tab-pdf) investigating the upper limit of what a human body can do indicated that both the intensity and duration of an event define the limits of tolerance before breakdown occurs. It appears that our ability to absorb calories and repair/build tissue is the key factor- with long term stress peaking at 2.2x our base metabolic rate (BMR). 

From a practical standpoint, you can run a 25-hour ultramarathon (8.5x BMR) or climb a mountain even though the energy demand for those activities is higher than 2.2x BMR-  because they are short duration events- usually between a few hours to a few days. Skiing across Antarctica for 40 days or through-hiking the Pacific Crest Trail for 140 days (3x BMR) months are moderate duration events, usually performed at lower intensities and requiring longer recovery periods. And then there’s pregnancy! 280 days in which women’s bodies create an entirely new human being and then breastfeed the baby afterwards. 

There’s literally no physiological system that pregnancy doesn’t affect- from huge increases in blood volume, cardiovascular demand, hormonal and endocrine shifts, immune system changes, growth of the fetus and musculoskeletal changes for the mother. Day after day after day! It turns out that the energy demand of pregnancy can top out right at the upper limit of what a human body can endure for 40 weeks- and that’s before the delivery- which either involves major abdominal surgery via C-section or trauma to the pelvic floor via vaginal delivery. 

I like to start with this amazing fact- because it puts into perspective the incredible accomplishment of pregnancy and delivery itself, and it explains why the recovery process after having a baby takes some time. Nobody asks a professional mountaineer two weeks after summiting the world’s toughest peaks (11 days at 6.6x BMR) when they are “getting their body back”. Nobody assumes that Tour De France riders (23 days, 5x BMR) can recover instantly. And- I bet they have the luxury of sleeping all night! 

There is great need and great opportunity for improving women’s health both pre- and post-partum. Many women receive the “ok” to return to activity 6 weeks after giving birth, but often with little to no guidance or support. Given that proper recovery takes as least as long as pregnancy does, this is a huge disservice to women- who are simultaneously sleep-deprived, physically exhausted and under a great deal of social pressure to “bounce back” ASAP. 

Every woman’s experience with pregnancy, delivery and postpartum recovery varies. Common problems include back pain, SI joint pain, postural changes, core and pelvic floor weakness, and stress or urge urinary incontinence. Many women also experience increased joint laxity for the first 6-9 months after pregnancy due to hormonal changes. These are all treatable! 

Physical therapists are uniquely able to help with pre and postpartum daily activities and exercising and this can make a huge difference in quality of life and for decreasing injuries. PTs are trained in restoring core muscle function, retraining posture and ergonomics and providing safe guidelines for gradually returning to exercising. Some PTs specialize in assessing and treating pelvic floor pain, dysfunction and urinary incontinence.  It’s reassuring to have this kind of support as part of your integrated medical team- and an option that Prevail PT can help you with!