Science Fact of the Day: Pregnancy and Strength Training

When I was a personal trainer I had always hypothesized that strength training would lead to positive outcomes for pregnant women and the child, particularly if they had been training prior to the conception of their child.

Since I’m not a research center and such training could be high risk, I just wouldn’t train a pregnant woman. The wisdom in the early 2000s was, “don’t engage in strength training if you’re pregnant.” Among trainers the wisdom was, “that doesn’t make any sense, but don’t do it to avoid a lawsuit.” Recently (2015) the American College of Obstetrians and Gynecologists said that it was safe to initiate/continue strength training during uncomplicated pregnancies.*

Anyway, strength training is getting closer and closer to being a scientifically verified panacea. In the case of pregnancy, strength training:

  1. Does not increase the risk of pre-term birth.
  2. May improve fetal heart function (circuit style training)
  3. Improves maternal energy levels
  4. Decreases risk of preeclampsia.
  5. Lowers risk of unhealthy weight gain (this one should have been obvious)
  6. Lowers risk of gestational diabetes
  7. Decreases incontinence by strengthening pelvic floor musculature
  8. Potentially decreases risk factors to the child caused by the mother being overweight
  9. Makes the mother feel healthier
  10. Decreases risk for post birth depression (exercise in general)
  11. Decreased back pain

Now, I’m no doctor and I’m not making any recommendations. But hopefully this information helps you do some of your own research.

*American College of Obstetrians and Gynecologists. Physical activity and exercise during pregnancy and the postpartum period. Committee Opinion Number 650 2015.

Punching Bags

It was finally cool enough to work out in our garage rather than at the gym.

Avery and I lifted weights and I hit the punching bag.

I increased the intensity of my blows just because I thought my hands had hardened up pretty well over the past several weeks. This resulted in two things.

My wife noted that hitting the punching bag looked pretty manly. She’s seen me dead lift and squat nearly 400 pounds in the same day and just gave me a fist bump. But watching me punch an invincible target that never gets hurt, tired, or offended looked manly. I know she’ll support me if I have to fight this guy:

It also resulted in some of my skin peeling off when I washed my hands later. It wasn’t from abrasions, it was just from pounding. It happens.

But then at church, somebody asked, “Who have you been punching?” “I don’t punch anybody,” I said. Silently, I reasoned that I was just exercising like a young man at the wrong age.

Fatigue and Heavy Lifting

When I was younger I used to train really hard. I still tend to do so. But when I was younger, I don’t even remember why, but I decided that it would be important to test my ability to lift insanely heavy weights under psychological distress. To simulate that state, I did what I hate the most: I ran. I would run 1.1 miles in the windless, midnight heat of Texas (I got off work at 12am back then). I would time it so my roommate could try to beat my time next time he ran. Then I would rest for 3 minutes or 1.5 minutes depending on the day and do a 20-rep squat or warm up to a 3X3 squat. I would then do deadlift, bench, chins, and a single of clean and press for fun. I only weighed about 135 back then because I could only afford, on average, about 1300-1500 calories a day.

In the last year I’ve bumped by dead lift up to 375 for easy singles and my squat up to 365 for the same. I’m not that strong at the moment because summer break comes with a whole list of challenges that make routine gym adherence difficult. I did buy some on-sale equipment for the garage though. That brings me to my point. On days when it is inconvenient to make it to the gym, I do some dead lift, ab roll outs, and heavy bag in the garage. But I decided: why not do dead lift under psychological distress like in the old days. Anyhow, I was doing 255 for reps after hitting the heavy bag for three three minute rounds. Then today I did a three minute round and two five minute rounds on the bag. It was about 91 degree out, but the heat index was 102. I could only pull 205 off the floor five times before I felt like collapsing.

Moral of the story: in door strength training is definitely good for you and most certainly to be preferred to other fitness craziness. But, if you want to test your meddle (while taking safety precautions for heat and fatigue) doing heavy weights in a state of metabolic and psychological distress will certainly indicate what you’re made of. I’ll look up research on this topic and post it later.

Baking Soda as a Sports Supplement?

One of the amazing things about the world is how seemingly disparate things are connected in profound ways. One of these connections is between sodium bicarbonate (household baking soda) and intense physical exertion.

I use Sodium Bicarbonate for my heartburn when it comes up (less common these days thanks to eating less carbs), but I never would have guessed that it functioned as an ergogenic aid.

But. these studies indicate that it does:

  1. Saunders, Bryan, Craig Sale, Roger C. Harris, and Caroline Sunderland. 2014. “Effect of Sodium Bicarbonate and Beta-Alanine on Repeated Sprints During Intermittent Exercise Performed in Hypoxia.” International Journal of Sport Nutrition & Exercise Metabolism 24 (2): 196–205.
    This study notes that Beta-Alanine and Sodium Bicarbonate combined or separate seem to have no effect on performance, but did have an effect on blood pH. The authors also admitted that other studies found results which indicated a positive effect on performance under different circumstances.
  2. Mueller, Sandro Manuel, Saskia Maria Gehrig, Sebastian Frese, Carsten Alexander Wagner, Urs Boutellier, and Marco Toigo. 2013. “Multiday Acute Sodium Bicarbonate Intake Improves Endurance Capacity and Reduces Acidosis in Men.” Journal of the International Society of Sports Nutrition 10 (1): 1–9.
    This study indicated that several days of acute doses of sodium bicarbonate prior to competition increased endurance performance and reduced acidosis.
  3. McNaughton, Lars R., Jason Siegler, and Adrian Midgley. 2008. “Ergogenic Effects of Sodium Bicarbonate.” Current Sports Medicine Reports (American College of Sports Medicine) 7 (4): 230–36.
    This meta-analysis shows sodium bicarbonate supplementation to be generally effective for increased athletic performance. It does note that roughly 10% of people tend to have intestinal distress due to its ingestion though. The analysis showed 10 studies which noted a positive effect due to sodium bicarbonate supplementation, 2 which showed decreased performance (both involving swimming), and 5 which indicated no effect.


I found several more studies indicating that the effect is positive and a few more that noted little to no effect or determined that individual differences may dictate response to the chemical. I don’t really have a desire to improve my exercise performance utilizing baking soda, but it may prove useful for athletes and casual people who train for pleasure or their well-being.

I’m not a doctor though so this blog can’t diagnose or treat diseases. Also, do note that you can overdose on the stuff. If you wish to see a more comprehensive review of the subject that does not require access to ebsco or a university library, Chris Beardsley reviews the literature here.

Scientific Research and Personal Experience

I did an experiment based on some new data I discovered about tendons. My 8 year knee tendinitis is gone. It had to do with exercising more frequently. I got a lot stronger in just 3 weeks also: the end.

Training Efficiently
In my own life experience, perhaps the safest and least time consuming way to pursue total body fitness is to train with somewhere between 6 and 12 exercises and train with perfect form, taking each exercise to a state of complete positive muscular failure, briefly resting and then moving to the next exercise. Your muscles are getting an intense workout, your hardest reps happen when the muscles are producing the least force (because they are tired) and none of the movements are “explosive” thus accelerating the weight to very high velocities and risking injury. During workouts of this nature your heart feels like it might explode out of your chest, you breath very hard, and your veins pump lava or pieces of broken glass. The problem with training this way, at least for me, is psychological. Every workout must be all out if you wish to make steady progress. Other problems are related to trying to plan for enough rest and when you train this way the metabolic demands are high. Research shows that muscle protein adaptations last for up to 21 days after the most recent bout of training. Energy system adaptations can begin to regress within 4-7 days. I wish I could remember where I found that data, but I remember everything but the name of the study and it’s authors…which means nothing. Nevertheless, training like every workout is a zero-sum game can be psychologically defeating. Also, the training is seldom enough that other types of adaptations apparently cannot happen (more on that later, as it is the point of the article).

Personal Story: Knee and Back Pain

When I was 20 I woke up one morning with very bad knee pain. This came right around the same time I seriously injured my back. I went to a doctor and received an x-ray on both offending pieces of my body. The knee pain was determined to be very serious tendinitis (probably from a knee collision in a jiujitsu match a while before). The back injury, which was missed in the x-ray but was confirmed by another doctor, was a torn ligament between a rib and one of my vertebrae (don’t remember which). Anyhow, I was told to lay off exercise for 6 weeks. If my knee still hurt, it was recommended that I start walking more than just at work and home to facilitate recovery for 6 more weeks. It was especially important that I do no squats or dead lift. If it still hurt, I was told to go back (maybe to get recommended for physical therapy). A weird series of events involving a car accident occurred which lead me to hit the weights again despite the pain about 3 months later. I was weak, fatter than I’d ever been, and my first set of squats did two things: left me gasping for breath and trying my hardest not to puke and when the muscle soreness my knee and back hurt less. TMy knee never stopped hurting, it just hurt less.

Research on Tendon Adaptation
Anyhow, fast forward to now and I started using Ebsco to do research through the public library (out of grad school so I don’t get my own key code anymore). I discovered that there have been several advancements in the knowledge of connective tissue adaptation since my time as an exercise science major. For instance, in 2007 a study was published (though with no control group) observing the effects of leg extension training on subjects doing heavy weight with one leg and light weight with the other. There were several interesting observations, but what was most pleasant to discover was that the patellar tendon actually experienced hypertrophy as well as increased stiffness (a good thing for joint health) in the leg trained with heavier weight:

In summary, the present study is to the best of ourknowledge the first human study to report tendon hypertrophy following heavy resistance training. Further, the data show that tendon hypertrophy to heavy-resistance training in the patellar tendon was related to the proximal and distal region, but not to the mid-region of the tendon.

Kongsgaard, M., S. Reitelseder, T. G. Pedersen, L. Holm, P. Aagaard, M. Kjaer, and S. P. Magnusson. 2007. “Region Specific Patellar Tendon Hypertrophy in Humans Following Resistance Training.” Acta Physiologica 191 (2): 111–21. doi:10.1111/j.1748-1716.2007.01714.x.

In the abstract of a literature review from 2006, I found that

For tendons, metabolic activity (e.g.detected by positron emission tomography scanning), circulatory responses (e.g. as measured by near-infrared spectroscopy and dye dilution) and collagen turnover are markedly increased after exercise. Tendon blood flow is regulated by cyclooxygenase-2 (COX-2)-mediated pathways, and glucose uptake is regulated by specific pathways in tendons that differ from those in skeletal muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as to some degree of net collagen synthesis. These changes modify the mechanical properties and the viscoelastic characteristics of the tissue, decrease its stress-susceptibility and probably make it more load-resistant.

Kjær, Michael, Peter Magnusson, Michael Krogsgaard, Jens Boysen Møller, Jens Olesen, Katja Heinemeier, Mette Hansen, et al. 2006. “Extracellular Matrix Adaptation of Tendon and Skeletal Muscle to Exercise.” Journal of Anatomy 208 (4): 445–50. doi:10.1111/j.1469-7580.2006.00549.x.

Several other studies report the same sort of results. The most interesting things to me are A) The increase in protein synthesis B) The increase in blood flow (which can provide nutrients for recovery) C) That actual hypertrophy can be stimulated in tendons D) that even body weight squats increase tendon stiffness in elderly and untrained populations. But what was most interesting to me on a personal level was that “collagen synthesis in human tendon rises by around 100% with just one bout (60 min) of acute exercise, and the elevated collagen synthesis is still present 3 days after exercise (Fig. 3; Miller et al. 2005). In skeletal muscle, the rate of collagen synthesis also increases with exercise, in a time-dependent manner that follows the increase in myofibrillar protein synthesis with exercise (Miller et al. 2005).” What this means for people who have had chronic tendinopathy, is hard to say. But what inferred that it could mean is that training with more frequency than I’m used to could increase the protein turnover rate in my knee and promote recovery. Given my own hypothesis that overuse injuries often come from explosive exercise and sudden acceleration of a limb which puts tremendous force on connective tissue despite low resistance, I decided that squatting more frequently with heavy enough weight to induce protein synthesis could help my knee.

I thus decreased my weight on squats, began using a high-bar Olympic depth, squat and hit the gym 3 days in a row during week one. Then week two I did the same thing and the weights that were very heavy using that style of squat went up very easily. I ended up squatting a personal best (345 pounds with no belt, no spotter, and no struggle) even compared to my wider power-lifting stance. This week I squatted five days in a row.

Starting Thursday morning I woke up with no knee pain. Today I still have no knee pain. Now, any number of things could have contributed to my apparent recovery after eight years of tendinitis. I could have just finally eaten enough protein, I could have finally slept enough, maybe I ate a magic vegetable like in a video game, it could be placebo though I imagine that would have fixed it years ago, or perhaps a wizard did it. But, the only variable I changed in my one subject sample group was exercise frequency. Now, my shoulders feel a bit beat up from squatting heavy for 5 days in a row. My lower back is pretty sore too. I certainly read less this week because the trips to the gym eat up evening time after work, but my knee feels better. I did chores around the house all morning and hardly noticed. Normally my knee remains in the fore on my consciousness when I’m picking things up, fixing things, or bumping it into stuff. It was unnoticeable today. I’ll tell you what happens in the future.


More on Weights and Training

As my previous post indicated 1 Rep Max indicators seem to produce fishy results as far as I’m concerned. This week I managed 265 for 20 reps in one set. According to a 1-RM calculator, I should be able to squat 441 for a single rep. By next week, if I can do 275 for 20 reps, I’ll be able, purportedly, to do 458. The evidence against this level of strength is clear. I can only squat 315 for a few sets of 3. Now, I don’t use a belt or squat shoes. I also have a genetic bone disorder that puts me at certain disadvantages in the weight room.

As a theorized, my body seems to be geared towards a form of endurance at high levels of effort and very quick recovery up to a point. For instance, I can do a set of fifty squat jumps, rest a couple of minutes and do a second set. Similarly, running a mile is an awful chore. But I can run several 40 yard dashes with a few seconds in between without feeling particularly tired. On a similar note,bike ride to work always has my legs burning when I’m only half-way there (it isn’t far). I suppose the explanation for this is in the fiber type distribution in my body. I’d attribute it to my training, but for months I’ve been training in low rep ranges (though I was injured) and making snail pace progress. By contrast, I decreased the weight, increased the reps to 20 reps per set and have made progress up to a weight that was challenging for me in low rep ranges in recent history. Perhaps as I end this brief foray into 20 rep squats to give myself a break from going heavy every work out, I’ll discover how much progress I can make at low rep ranges without an injury.