chest-blast-experiment-resuWhat would you say if I told you you could add 2 inches to your chest, maybe more, in a week?

That’s precisely what happened to a bunch of volunteers I recently had go through an insanely intense chest workout (up to 3 times a week).

CoverandCDSmallI devised this program based on the results of a similar protocol I called the Arms Blast Experiment, where “lab rats” gained an inch, sometimes more, within 7-10 days. I knew that if I took the same principles behind the Arms Blast and apply them to the chest, I could create something very special.

I put the call out on November 12th 2014 and had hundreds of guys and girls volunteer.

I wanted a group of 30 subjects to make the study manageable. I selected 30, but by the time the experiment was due to begin, some guys dropped out, and others simply didn’t respond to my email informing them they had been selected.


  • got injured prior to the blast
  • said it was thanksgiving and not a good time for them (why did you volunteer in the first place?)
  • were cutting and didn’t think the timing was appropriate (why did you volunteer in the first place?)
  • perhaps didn’t receive my email as it hit their spam box
  • looked at the workout and realized they didn’t have the balls spine for it.

Regardless of the smaller sample size, get this…

* Not a single person didn’t gain – and gain spectacularly *

NOTE: The Chest Blast Experiment program will be available for digital download on Monday 16th February!

So, here goes: A full list of final results and testimonials from the Chest Blast “lab rats”.

I have included pics, full names, age, location ,and facebook profile, where I have been given permission to do so. Some did not wish to give details, which I have to respect.




FJ Labuschagne

FJ Labuschagne, 34 yrs old (his facebook here)  GAINED 5cms or just over an inch

Measurements as at 24 November 2014: 103 centimeters

I am a former varsity rugby player and although my legs and arms are muscular, I always had trouble with my shoulders and pectorals being stubborn.

Final workout done and dusted. Here is the gist: shock and awe.

I am a hardgainer, only when it comes to my pecs. Expecting one or two cm growth in a six month cycle is or was ambitious.

I started out at 103cm. Today I am at 108cm. I can see a thickness and I can see it showing through my shirts. Thank you!



Andy, 34 years old, in Australia, GAINED 2 inhces.

Howdy…Below this is the result of the Chest Blast workout:

Before start the training on Monday 24 November 2014, my chest measurement was 37″. On Sunday it is now 39 inches.

The workout is insane, but it’s good to take me out of my comfort zone. My hands were shaking after the 1st and 2nd sessions. The 3rd session I wanted to quit, but in the the end I finished it.
All the soreness is crazy.



Al Siebert, 48 yrs old, in Surprise Arizona (his facebook hereGAINED 3/4 inch.

45 inches to start. 45 3/4 finish. That was 8 days later. The workout was insane, fun and challenging. Loved the huge pumps during the routine and to gain 3/4″ in size after years of working out, I think is unbelievable.

The soreness is comparable to having taken a couple of weeks off or to have never worked out.

Obviously never had this type of gain in such a short period of time. The different routine was a blast (pun intended).

Since posting you a picture of my Total Six Pack Abs results 4 years ago, I have gained 25 plus lbs. following your MANS, TSPA diet and THT workouts.

If any of you are out there reading this that have just started MuscleHack’s routines, STICK with it! You will not be disappointed. As always Mark, Thank you very much for putting all this information and your wisdom out there. You are the man! Al

Al before the Blast

Al before the Blast




MuscleHack Forum user “bbHULK” GAINED 2.75 Inches

Measurements before the workout:48 inches

Now after doing the Chest Blast on Monday and Friday, chest on Saturday is 50.78 inches

(this “blaster” did just 2 workouts. There are options for 2 or 3 workouts during the week).



JJ DeBeer

JJ DeBeer

JJ De Beer. 19 years old in Pretoria, South Africa (his facebook here) GAINED 3 Inches.

*JJ gets the prize fort the best results of the blast*

23rd November before workout measurements = 48 inches

After chest blast on Monday & Friday, my chest now = 51 inches

The program was Intense and the pump was insane. I loved it the results. As I approached the end of the workout my pectorals were on fire. Must say one of the best workouts I ever completed.



Clara, 47yrs young in London, UK. GAINED 1.5 inch

(the only female who completed the blast)

Hey Mark, so I managed to get in 3 sessions- Mon 24th November, Thursday 27th Nov, and today. After the first session I was extremely sore until Thursday. Thursdays session was therefore a struggle due to soreness.

My chest still feels tight with visible upper pec development. That’s all you can see on a woman! Lol! My anterior delts and arms both feel tight and have visibly improved in shape. Here’s the info you require:

Chest size BEFORE and AFTER:

  • Session 1- 34″
  • Session 2- 35″
  • Session 3- 35.5″

REALLY REALLY enjoyed this workout. I have never been challenged like this doing a chest workout. For women I would say if you want to develop a nicely shaped upper body this is for you!

The results are amazing! I really didn’t think you could make such a difference in measurements and aesthetics in 1 week!

In terms of soreness I have one comment…. Insane. After my 1st session my upper body was so sore that even coaching my clients was a struggle.

As mentioned earlier I loved this workout and was honoured to have been picked as a guinea pig! Thanks Mark and keep up the good work!!




Joe Vorndran

Joe Vorndran. 42 years old in Fort Wayne, Indiana, USA.  (his facebook here)  GAINED 0.5 inch

From 40 to 40.5 inches as of today

The workout itself is great, no issues there. The question is, how often can you do it? For me I think I would only do one of these blast routines once every couple months.






Richard Freeman, , 40 yrs old, in Bristol, UK. GAINED 2 Inches.

…BUT the IMPORTANT news is my chest was 41 inches before, and 4 days after my 2nd workout, it was 43 inches.

I could obviously feel and see the pump I had, about 30 hours after workout, and the numbers don’t lie either.




Justin Brown

Justin Martin, 25 yrs old, from Lexington, Kentucky in the U.S. GAINED 1 inch.

I am the Personal Training Director at a gym in the city. I’d rather people not get on my facebook, but you can have a picture. Thanks again I really appreciate it man. Glad I could participate and help you in your study!

Nov 24, 44″ first workout
Nov 25, 44″
Nov 26, 44 1/8″
Nov 27, 44 1/4″ second workout
Nov 28, 44 1/4″
Nov 29, 44 3/8″ last workout
Nov 30, 44 3/8″
Dec 1, 44 1/2″

This was one of the hardest workouts I’ve ever done. I was the sorest on days 2 and 3 after my first workout. The second workout felt great. The last one was a challenge as my chest muscles and anterior delts just felt extremely fatigued. So far 1/2″ so completely worth it. If you want to add quick size in the chest this is the workout. Thanks Mark! I’ll keep posting any gains over the next few days.

45″ as of Saturday, which was exactly a wk from last workout. That’s another 0.5″!



Michael Breen

Michael Breen

Michael Breen, 37 yrs old in County Armagh, Ireland. GAINED 2 inches (his facebook here)

Chest Blast was completed on Tuesday and Friday.

Chest 24th November 2014 – 44 ¼ inches

Chest 30th November 2014 – 46 ¼ inches

The Chest Blast experience was extremely good and painful but overall really pushed me to the limits.  I found the first day Tuesday tough and for 2 days after very sore in between the THT routine.

The best sets for me where sets 2, 3, 5, 6, 7, 8.  Sets 1 & 4 were good but the others pushed me that bit and I feel that’s how the gains happened.

Now Mark you have a Arms & Chest Blast you can now develop Blasts for Shoulders/Back/legs/abs?




Reza Kairimi

Reza Kairimi, 34 yrs old in Canada. (his facebook hereGAINED 2.5cm

Hi Mark! Here are my results:

Before 94 cm and after 96.5 cm

My pecs are looking visibly fuller in the middle to lower part of the chest and towards outer portion of the pecs. They also feel noticeably denser when I poke them.

The workout is absolutely intense! I loved it! It made me to go harder on THT workout since now I pushed through the pain no matter what lol…as they say this is the mind that gives up first before the muscle.

During the workout, not only were my pecs pumped up, but my shoulders were looking huge at the same time. I felt so tight in the respective areas.

Thank you for all the methods you have been coming up with and sharing them with us.




Sean Brown

Sean Brown

Sean Brown from Corinth, Texas, USA (his facebook hereGAINED 1.5 inches

Mark, here are my results from the blast:

  • Starting measurement 11-23-14: 43.5 inches (before)
  • Monday 11-24-14 – day of first Chest Blast workout
  • Tuesday 11-25-14 Chest size: 44.25 inches
  • Wed. 11-26-14 Chest Blast
  • Thursday 11-27-14: Chest size:44.65 inches
  • Friday 11-28-14: Chest Blast
  • Saturday 11-29-14 Chest size: 45 inches even.
  • As of December 3rd: Chest size 45 inches

My gains stayed!! Very happy with how this turned out!!




Simon Kirk in Auckland, New Zealand (his facebook here) GAINED 4.5cms or 1.75 Inches

Simon Kirk

Simon Kirk

Day one was awesome, great to change up my workout and felt a huge pump.

The second day was painful, my chest was on fire, I could hardly believe how sore I was, I love that feeling, I just couldn’t wait to push the next set out, (I know I’m crazy).

Overall, great workout and I saw at least 4-5cm of gains

Thanks Mark




Steve Zeiger, 51yrs old from Cairns, Queensland, Australia. GAINED 2cms. (his facebook here)

*note: this subject was cutting/on reduced calories at the time of the blast.*


Steve Zeiger

Using Mark McManus’ “Chest Blast Routine” my chest measurement increased 5 cm in 7days. Not bad for a 51 year old! My chest has always been a “hard gain” body part for me.

The workout uses techniques I have not seen anywhere else in almost 30 years of gym training. I cannot recommend the programme highly enough.

I have been weight training since I was 23 and never have I seen such an effective routine and diet.

Also I am in the middle of a Total Six Pack Abs diet and routine, so who says you can’t lose fat and build muscle simultaneously?


As Steve said above, this training package will include techniques you’ve never used or even heard of before.

Excited for some serious pec growth? You should be! 😀

Again, this “hyper-intense” program will be available for digital download on Monday 16th February. 

I have a countdown timer in the sidebar of this site to remind you 😉

Get ready!

Train With Intensity!


P.S. In the meantime, put your feet up and listen to the first MuscleHack podcast ‘4 keys to igniting new gains’.

You'll love your fast gains on THT!

Cool! Click here to take you to the download page. (or check your email for the download link)

You'll love your fast gains on THT!

Cool! Click here to take you to the download page. (or check your email for the download link)