Thursday, June 17, 2010

Creatine is Sexist, Fasted Training, and A Vitamin D Video

Ok, Ok!

So I took a wee bit of a longer break than I thought I would; I was back home on the 10th, but pretty much every weekend I have off I'll be traveling this summer, so I had some domestic catch-up to do---plus, my computer literally died the day before I left, and I lost a TON of great studies and nutrition material.  Boo.  I have a shwanky new desktop running Windows 7 (versus the boat-anchor that died), so I'm a happy, albeit disorganized, camper.

  Anyhoo, onto the goodies.  I've got a couple of interesting studies with some gender-specific considerations, and an entertaining lil' vid on vitamin D.

Creatine.  It's in there, trust me.

J Strength Cond Res. 2010 Jun 10. [Epub ahead of print]

The Effects of Creatine Loading and Gender on Anaerobic Running Capacity.

1Metabolic and Body Composition Laboratory, Department of Health and Exercise Science, University of Oklahoma, Norman, Oklahoma; 2Applied Biochemistry and Molecular Physiology Laboratory, Department of Health and Exercise Science, University of Oklahoma, Norman, Oklahoma; and 3Biophysics Laboratory, Department of Health and Exercise Science, University of Oklahoma, Norman, Oklahoma.


Creatine (Cr) loading consists of short-term, high-dosage Cr supplementation and has been shown to increase intramuscular total Cr content. Increases in body weight (BW) have been shown to result from Cr loading, with differences by gender, and increased BW may impact weight-bearing exercise. The critical velocity (CV) test is used to quantify the relationship between total running distance and time to exhaustion. The CV test provides the variable, anaerobic running capacity (ARC), which is an estimate of the anaerobic energy reserves in muscle. The purpose of this study was to examine the effects of gender and Cr loading on ARC. Fifty moderately trained men and women volunteered to participate in this randomized, double-blinded, placebo (PL)-controlled, repeated-measures study. After a familiarization session, a 3-day testing procedure was conducted. A maximal oxygen consumption test (&OV0312;o2max) on a treadmill was performed on day 1 to establish the maximum velocity (Vmax) at &OV0312;o2max and to record BW. Days 2 and 3 involved treadmill running at varying percentages of Vmax. Participants were randomly assigned to either the Cr or PL group and received 20 packets of the Cr supplement (1 packet = 5 g Cr citrate, 18 g dextrose) or 20 packets of the PL (1 packet = 18 g dextrose). After consuming 4 packets daily for 5 consecutive days, the 3-day testing procedure was repeated. The male Cr loading group exhibited a 23% higher (p = 0.003) ARC compared to the PL group. Nonsignificant BW increases were found for the Cr groups. These findings suggest that Cr loading may be an effective strategy for improving ARC in men, but not in women, and revealed only nonsignificant increases in BW. Creatine loading may be used before competition by athletes to provide improvements in high-intensity, short-duration activities.
PMID: 20543729 [PubMed - as supplied by publisher]

My Thoughts:  I think everyone probably knows my overall thoughts on creatine, as per some of my previous posts; it's effective, it's cheap, and it works.  But I find it interesting that the female control group didn't exhibit an increase in anaerobic capacity; many previous studies have found performance increases in BOTH genders.  Perhaps it's the fact they used creatine citrate versus phosphate or monohydrate, the most commonly available forms.  I can only speculate, since I don't have access to the full study. Once again, though, it's obvious is works well for anaerobic activity.

Maybe.  Maybe Not.

J Sci Med Sport. 2010 May 6. [Epub ahead of print]

Adaptations to skeletal muscle with endurance exercise training in the acutely fed versus overnight-fasted state.

Institute of Food Nutrition and Human Health, Massey University, Palmerston North, New Zealand; School of Exercise and Sport Science, University of Sydney, Lidcombe, Australia.


Minimising carbohydrate (CHO) status in the peri-training period may accelerate the training adaptations normally observed. The aim of this study was to compare adaptations to endurance training undertaken in the acutely CHO fed and overnight-fasted states. Eight female and six male untrained, healthy participants: aged 26.6+/-5.8 years (mean+/-SD); height 174.7+/-7.6cm; weight 75.3+/-11.4kg; VO(2max) 3.48+/-0.67l/min; were randomly divided into two training groups and undertook four weeks of five days per week endurance cycle ergometer training in either the overnight-fasted (FAST) or acutely fed (FED) state. FAST training had no effect on RER or plasma glucose, lactate and FFA concentrations during subsequent submaximal exercise. Training-induced changes in Vastus lateralis citrate synthase (CS) and 3-hydroxy-CoA dehydrogenase (HAD) activities were not different between training groups (P=0.655 and 0.549, respectively), but when the effect of gender was considered, men responded better to FAST and women responded better to FED. The FAST group showed a significantly greater training-induced increase in VO(2max) and resting muscle glycogen concentration than FED (P=0.014 and P=0.047 respectively), but there was no gender interaction. In conclusion, these results suggest that (a) meal ingestion prior to daily exercise can modify some of the exercise training-induced adaptations normally seen with endurance training compared to when daily exercise is undertaken in the overnight-fasted state; and (b) the extent of these adaptations in skeletal muscle differ slightly between men and women. Copyright © 2010 Sports Medicine Australia. All rights reserved.
PMID: 20452283 [PubMed - as supplied by publisher]

Now THIS is a really interesting study; a couple of dudes much, much smarter than me have already looked at it, and broken it down nicely.  Martin Berkhan from LeanGains broke it down in it's entirety, and Alan Aragon recently reviewed it with a fine-tooth comb in his monthly research review.

Quick Points:
  • Fasted training caused an increase of +%50 muscle glycogen POST-workout
  • Women had better parameters when FED; Martin breaks this down nicely. 
  • The study size was small, and in untrained subjects.
My Thoughts:
While the study has issues, I think it definitely lends credence to the idea of "train low, compete high", in regards to nutritional fueling.  Should one run out after their very first 16 hour fast and try and crush a 5km run?  Hell no!  One topic not addressed is RPE (Rate of Perceived Exertion).  Training fasted greatly increases this proportional to intensity.  The first time I tried a fasted training session, I decided on 400m sprints.  It was an eye-opener, to say the least.  Personally, I'll be re-visiting this leading up to my 24 hour race.

If you have your diet, training, and lifestyle habits dialed in, give it a try.  IF (intermittent fasting) is a crazy interesting topic, which some folks swear by for performance, body composition, and general overall health.  It's also a very easy way to totally sabotage your training.  And if you're female, you may just want to say "To Hell With THAT!", and you may just be justified!

I know I've been ranting about a nice, juicy vitamin D post, but in all honestly, the topic is so massive, it's daunting. Plus, every week there is new material published. Like this video. So, in the meantime, sit back, grab a cup o' java, and enjoy:

Recent Training

June 2nd-9th
Kamloops, Whistler, daily sessions of XC and DH mountain biking.
Longest ride was 5 hours, shortest would be a 10 minute screaming-downhill run. While there was some pretty significant caloric expenditure, I can GUAR-AN-TEE there was significant caloric repletion, post-ride. :)

June 11th, CFLA, 12PM
Power Clean, 5x5, 155#. After riding for a week, my back was fried from being hunched over, and my quads were mush. Some pulling work was needed, minus the Oly squat

AMRAP in 12 Min:
10 Sledgehammer Hits (12#)
10 C2D pushups
10 Box Jumps (20")

7 Rds + 13. Really liked this WOD, which was CFLA programming from few days earlier.

June 16th, CFLA, 1PM
"Smoke Break Cindy" ---props to Glen for the perfect name for this!
5 rounds of 2 minutes per round
1 minute rest between rounds

5 Pull Ups
10 Push Ups
15 Squats

16+4 rounds. I kind of de-legitimized my effort, but with good intentions; I set a chest marker for my pushups to hit 90 degree flexion, so I wouldn't go shallow. In hindsight, I should have just done C2D, and not worry about the number of rounds I was hitting. In the later rounds, I don't think I was hitting a full 90, due to my hand width. Regardless, this was a great version of the classic Crossfit workout "Cindy"