Weekly Research Discussion: MCTs

[romistrub]

I've edited the abstract for clarity of key points.

Effect of Ingestion of Medium-Chain Triacylglycerols on Moderate- and High-Intensity Exercise in Recreational Athletes

Naohisa NOSAKA, Yoshie SUZUKI, Akira NAGATOISHI, Michio KASAI, Jian WU and Motoko TAGUCHI (2009)

Background

Medium-chain triacylglycerols (MCT) are known to hydrolyze readily and completely to fatty acids and to be metabolized more easily by β-oxidation than long-chain triacylglycerols (LCT).

Methodology

Subjects: 7 women, 1 man, 21 to 28 years old. Constant lifestyle pattern undertaking continuous exercise. Members of a physical education college.

Test food: 4.8 g protein, 67.6 g carbs, 14.4 g fat (6 g MCT (74% caprylic acid, 26% capric acid) or 6 g LCT) ingested once per day for 14 days.
Other food: 52-58 g protein, 65 g fat, 250-255 g carbohydrate (dietary intake did not otherwise differ significantly between groups).

Test: After 14 days of ingestion of either LCT or MCT test food, subjects consumed test food 1 hour prior to cycle ergometer exercise at 60% VO2max for 40 min followed by 80% VO2max until exhaustion. Blood lactate concentration, VO2, VCO2, and rating of perceived exertion (RPE) were measured at rest and during exercise.

Results

• The time to exhaustion at 80% VO2max was significantly longer in the MCT trial (10.2±7.6 min) than in the LCT trial (5.8±3.3 min).
• Blood lactate concentration and RPE during exercise were significantly lower after ingestion of MCT-containing food.
• Fat oxidation rate was higher and carbohydrate oxidation rate was lower during exercise in the MCT trial than in the LCT trial, but the differences were not significant.

Discussion

These results indicate that the ingestion of MCT-containing food may suppress utilization of carbohydrate for energy production because of increased utilization of fatty acids for generating energy.

Conclusion

Data suggest that short-term ingestion of food containing a small amount of MCT suppresses the increase in blood lactate concentration and RPE during moderate-intensity exercise and extends the duration of subsequent high-intensity exercise, at levels higher than those achieved by ingestion of LCT-containing food.

[romistrub]

What I find pretty incredible is that time-to-exhaustion was almost doubled with a very subtle change to dietary intake.

Some notes:

- It seems like they were all Japanese. If genetics plays a role in the response (I'm not familiar with these things), then it may not be applicable to many of us here.
- Mostly women, as well. Women are known to metabolize fat differently than men.

- The meal was ingested 1h pre-workout -- the 14 day "load" period may have been unnecessary.
- The pre-workout meal was high-carb. The effect may not appear if pre-workout MCTs were ingested alone.
- The diet was moderate fat, high carb. This effect may not be prevelant for high fat diets.

- MCT composition may play a role. If it does, coconut oil is only 7.8% caprylic acid and 6.7% capric acid, which would necessitate 57 g of coconut oil to meet the same absolute MCT intake in this trial. Pure MCT oils (e.g. MCT Maxx) typically contain 100% capric/caprylic acid, although they do not reveal the ratio.

[MuyThaiFighter]

Thanks for posting. I just recently upped my MCT intake to 3 TBSP per day. My last few workouts have been pretty damn good compared to pre-MCT. I also lowered my carbs to < 50g per day. I'm gonna continue for the next couple months to see how it goes.

[scottm]

Good info ... I also went from just using coconut oil for cooking to taking a few tablespoons a day.

[Vedic]

Myself and clients have never found MCT's to work in what they say they will do. it's fine if it's part of a food source etc.. But to supplement with them is pointless.

[MikeMartial]

Awesome stuff, Romi. Consuming MCTs is one way to put yourself into ketosis WHILE still consuming carbs. The rapid shift in substrate utilization makes it a great preWO supplement. My own use of MCTs, in the form of coconut oil, has creeped up every month. Seems I'm putting it in everything these days.

Dr. BG has some great thoughts on MCTs, although specific to body comp and not athletic performance:
Animal Pharm: Body Fat Loss: Saturated Fat Kicks the Cr*pola Out Of Olive Oil

[MikeMartial]

Originally Posted by Vedic

Myself and clients have never found MCT's to work in what they say they will do. it's fine if it's part of a food source etc.. But to supplement with them is pointless.

A bit OT: I've committed to doing 24hrs of Adrenaline next year, Vedic, so I'll be following your progress in PM Journal...when the heck is the next article coming?

[Vedic]

Next month. Had some personal issues to deal with, and school. So ya, next month. Don't get me wrong it's interesting to read about MCT's. But to supplement with them is just not how we train. None of us go for ketosis.

[Monger]

I wouldn't put that much stock in this. Look at the SD for the group results. Add that to the low participant group and it sounds like results were all over the fucking place. I looked at the study to find time to exhaustion per person but it doesn't seem to be available.

I mean, let's be realistic here. 6g of any nutrient, let alone MCT's, is not going to double time to exhaustion on anything.

[Monger]

Originally Posted by MikeMartial

A bit OT: I've committed to doing 24hrs of Adrenaline next year

What's that?