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Should You Have Sex The Night Before a Race? Fitness Wisdom from “Which Comes First, Cardio or Weights?”

Quick note: I’m accepting one more runner into my Full Coaching program. If you’re interested in working with me on a 1-on-1 basis, email me and let’s chat.

I just finished Alex Hutchinson’s book Which Comes First, Cardio or Weights? Fitness Myths, Training Truths, and Other Surprising Discoveries from the Science of Exercise.

Which Comes First, Cardio or Weights?

Instead of a full review, I thought it would be more interesting to post four questions that are answered in the book. Big thanks to author Alex Hutchinson for allowing me to publish my summary of his writing.

If you enjoy these Q&A’s, the actual book has over 110 questions about general fitness, endurance training, weight loss, and strength training answered by the latest scientific studies.

Now, I wasn’t a science major. I have no interest in reading complex studies that report on the electromyographic activity of the leg extensors. Most people just don’t have the attention span for that type of reading.

Luckily, Hutchinson clearly explains the science behind some of our most pressing questions (Should I exercise when I’m sick?) in one of the most easy to read books I’ve bought recently. With each Q&A only 2-3 pages, the book is perfect to read in short spurts if you can’t devote a long stretch of time to reading.

The answers below are my summaries in my own words. The full answers in the book are longer – and probably better written 🙂

Should I have sex the night before a competition?

Enter any college locker room and you’ll probably hear this debate. There’s not a lot of research on this but a few studies have shown no difference on subjects who had sex before exercise tests on grip strength, reaction time, stair-climbing, balance, and treadmill running.

A “typical” sex sessions (I’ll leave the definition of this to other blogs…) burns the equivalent calories of climbing two flights of stairs so I’m not surprised there’s no measured effect on performance. A cautionary note about the research: only men were studied. There’s no information on the effect of sex on women’s performance.

Ultimately, as long as you’re getting a good night’s sleep before your competition it looks like you’re not sacrificing your performance. Sex can dramatically affect your mood, so ensure you’re in the right mental state before your race. Some people need to be calm and collected, while others like to rage out to heavy metal and be in a more aggressive state of mind.

To quote New York Yankees manager Case Stengel, “It’s not the sex that wrecks these guys, it’s staying up all night looking for it.” That’s exactly what my college cross country coach told us!

Do I run wrong?

Everyone talks about fixing your form (I sure have!) to be a more efficient and less injury-prone runner. But you need to figure out if correcting your running form is possible and if so, will it do any good?

The answer to the first question is that yes, you can definitely learn how to run differently. But the answer to the second question is more muddled. It’s not entirely clear from the existing research if changing your running form will prevent more injuries or make you a more efficient runner.

What does seem clear is that the less experienced runners in the studies showed more improvement in running economy (efficiency) than the more experienced runners, who actually had lowered running economy scores. So if you’ve been running for years, that trial and error approach to being efficient could be the best way of running properly.

If you’re a new runner, you may be able to alter your form and become more efficient. But the best way of improving your form may just be trial and error through years of practice.

How can I avoid muscle cramps?

The conventional wisdom is that muscle cramps are caused when you’re dehydrated and you’ve lost too many electrolytes through sweating. While the research isn’t 100% at this point, it looks like this isn’t exactly why you get muscle cramps.

Instead, studies are showing that it’s a combination of fatigue and damaged muscle fibers that actually cause you to cramp. When you’re in the final miles of a marathon, for example, your muscles are incredibly fatigued and becoming damaged by the amount of work they’re doing. So they cramp.

Digging deeper into this theory is the idea that there’s a neural component as well, meaning the signals that your muscles get to contract (versus relax) from your brain actually increase when you’re very tired. Stretching the affected muscle is effective at ending the cramp because it helps it relax.

So how do you avoid cramps in the first place? Start by training adequately for your race so you’re not overly fatigued near the end. You can also taper more and set realistic goals so you don’t start too fast. But since the research isn’t entirely conclusive, go ahead and take in those electrolytes if you think they help. While you probably don’t need a salt stick, stick with what has worked for you in the past.

Will I Get a Better Workout if I Hire a Personal Trainer?

You may think that if you do the same workout routine as someone with a trainer, you’ll get the same benefit. But several studies show that you won’t.

In one example, two groups of men went through identical 12-week programs with the exception that one group had a trainer. At the end of the study, the group with the personal trainer gained 32 percent more upper-body strength and 47 percent more lower-body strength. The critical ingredients the trainer provided were motivation and increased ambition to lift more weight later in the program.

Most people tend to plateau with their workout plan and don’t add more weight, run more miles, or increase their intensity. A personal trainer or coach helps you set ambitious goals and push yourself harder. You can get similar benefits by having an enthusiastic training partner or running with a team. Beginners can get even more benefits with a trainer because they’ll learn more about their exercise program.


Again, thank you to Alex Hutchinson for letting me post the questions from his book. You can check out the book on Amazon or read his terrific blog at Sweat Science.

Another reminder that I’m accepting one more runner into my coaching program. Shoot me a line or check out the coaching page if you’re interested.

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