The Heartbeats of America
"Be Still, My Beating Heart" [The Moving Crew, Sept. 13] answers all my questions and quells my anxiety. I was wondering why during running my heart rate could soar to 193 beats per minute when my maximum heart rate established in spinning was 187.
Thanks also for mentioning about the "talk test." I won't worry about the numbers anymore. As long as I can recite the Pledge of Allegiance smoothly, I know my heart is okay.
That was a great piece. Sometimes you think you're the only one experiencing things -- you think you're weird, a hypochondriac, just getting older or even ill. Then you read something like this and it all makes sense.
My heart beats fast, too, when I do cardio. When I was younger I never gave it a second thought. Then I started paying attention to the heart rate stuff and got really scared because my heart rate just would not stay in the "right" range for my age. My doctor said I was fine, but the machines said differently. So, I stopped doing cardio.
It's been probably a year and a half now. I've gained weight and I miss doing my LifeStep. No more now! I'm starting my cardio again knowing that I can feel comfortable about my heart rate.
I was particularly interested in your discussion about a means for approximating one's maximum heart rate. As a long-time runner, I was aware of the widely used formula that uses 220 minus one's age as an approximation of HRM (although I learned that it was 230 minus age); and that training at roughly 70-80 percent of HRM provides for a near optimal cardiovascular "training effect." But I have also read that this formula is not considered appropriate for "trained athletes" so, your variation: 217- 0.85 (age) would seem to afford a closer approximation. But, wisely, you also acknowledged that this "still doesn't account for genetics."
My personal numbers in this realm provide an example of the limitations of your amended:
I started running at age 38, in 1967. Seven marathons, numerous 10 Ks and other races, and 20,000 miles later, at age 76, I'm still at it; but now running only 2-3 miles, four times a week, at a 10-minute pace. Yesterday, for example, at the end of a three-mile run, my pulse measured 140. Applying your amended formula provides a calculated HRM of 152. My 140 rate would place me at about 92 percent of my theoretical maximum rate, which would seem excessive.
However, another measure often used for avoiding over-exertion is heart rate recovery time following sustained exertion. The guidance that I long ago read about, and have applied, is: If your heart rate has recovered to about 100 beats per minute within three minutes after stopping your run, you are not training excessively hard. Lesson: Individual differences limit generalizations.
Abstinence Should Be Plan A
"Is Plan B 'Unsafe'?" [Sept. 6] tried to make the case that Plan B is safe for teens' or anyone else's use without medical supervision. Yet the claims for reducing teen, or any, unplanned pregnancy are not supported when one reads the entire article on which the story's claims are based.
The study authors analyzed a subset of adolescents, 45 percent of the women who attended four family planning clinics in San Francisco. The study group had been given three different forms of access to Plan B tablets. The "advance provision" group received a supply of emergency contraceptive pills. The "pharmacy access" group received a card which entitled them to receive emergency contraceptives free of prescription or cost at pharmacies, while the "clinic access" group had to go the clinic for supplies.
There was no significant difference in behavior or outcomes between the teens and the adults, except a higher pregnancy rate: The 10 percent pregnancy rate reported for the teens was nearly double than that for the adult participants (5.8 percent), and it does not compare well with the national 5 percent teen pregnancy rate.
More than 50 percent of the teen participants engaged in "unprotected" intercourse despite the benefit of their prior education in the clinics. Emergency contraceptives were used by 44.3 percent of those who had advance provision, 29.8 percent of those with pharmacy access and 28.9 of those with clinic access. While their 13 percent sexually transmitted infection rate (they were only tested for herpes simplex type II and chlamydia) was no higher than that of the adult study participants, it is a rather low standard to meet.
It is not necessary to assume that once teenagers have begun sexual activity the best one can do is to protect them against unplanned pregnancy and sexually transmitted infections. We have found that teaching teens to understand and value their fertility supports primary as well as secondary abstinence. The rate of sexual experimentation in our Teen STAR programs was 8.8 percent for males, 3.4 percent for females. Twenty percent of previously sexually active teens discontinued intercourse over the course of the seven-month program.
Hanna Klaus, MD
Natural Family Planning Center
and Teen STAR Program
Swimming Through Rough Waters
I've never been a Masters swimmer ["Into the Deep End," Sept. 6], but I have been a three-times-per-week fitness swimmer since 1979. It has gotten me through:
Numerous knee injuries, including an ACL injury and meniscal tears;
Two years of failed fertility treatments;
Two bar exams (passed both on the first try);
A successful high-risk pregnancy in my forties; and
A stress-related gastrointestinal problem.
It is so utterly boring, yet it is the perfect Zen exercise. I recommend it highly to everyone I know.