EMG Studies on Muscle Groups

[Darkhorse]

I found this post over on another board. Very interesting.

The results of the EMG studies show which exercises produce the greatest amount of stimulation within each target muscle group. The following table displays these results.

IEMG max motor-unit activation

Exercise/% EMG Muscle Stimulation

Pectoralis major:
Decline dumbbell bench press - 93
Decline bench press (Olympic bar) - 89
Push-ups between benches - 88
Flat dumbbell bench press - 87
Flat bench press (Olympic bar) - 85
Flat dumbbell flys - 84

Pectoralis minor:
Incline dumbbell bench press - 91
Incline bench press (Olympic bar) - 85
Incline dumbbell flys - 83
Incline bench press (Smith machine) - 81

Medial deltoids:
Incline dumbbell side laterals - 66
Standing dumbbell side laterals - 63
Seated dumbbell side laterals - 62
Cable side laterals - 47

Posterior deltoids:
Standing dumbbell bent laterals - 85
Seated dumbbell bent laterals - 83
Standing cable bent laterals - 77

Anterior deltoids:
Seated front dumbbell press - 79
Standing front dumbbell raises - 73
Seated front barbell press - 61

Biceps:
Biceps preacher curls (Olympic bar) - 90
Incline seated dumbbell curls (alternate) - 88
Standing biceps curls (Olympic bar/narrow grip) - 86
Standing dumbbell curls (alternate) - 84
Concentration dumbbell curls - 80
Standing biceps curls (Olympic bar/wide grip) - 63
Standing E-Z biceps curls (wide grip) - 61

Triceps:
Decline triceps extensions (Olympic bar) - 92
Triceps pressdowns (angled bar) - 90
Triceps dip between benches - 87
One-arm cable triceps extensions (reverse grip) - 85
Overhead rope triceps extensions - 84
Seated one-arm dumbbell triceps extensions (neutral grip) - 82
Close-grip bench press (Olympic bar) - 72

Latissimus dorsi:
Bent-over barbell rows - 93
One-arm dumbbell rows - 91
T-bar rows - 89
Lat pulldowns to the front - 86
Seated pulley rows - 83

Quadriceps:
Squats (parallel depth, shoulder-width stance) - 88
Seated leg extensions (toes straight) - 86
Hack Squats (90 degree angle, shoulder-width stance) - 78
Leg press (110 degree angle) - 76
Smith machine squats (90 degree angle, shoulder-width stance) - 60

Hamstrings:
Seated leg curls - 88
Standing leg curls - 79
Lying leg curls - 70
Stiff Legged Deadlifts - 63

Calves:
Donkey calf raises - 80
Standing one-leg calf raises - 79
Standing two-leg calf raises - 68
Seated calf raises - 61

This doesn't mean that some of you newbs out there need to completely scrap your programs just because of these results. For instance, it says the pecs get the best stimulation with the decline dumbbells, however, everything else is too close to it to make a noticable difference. From what I see, you also need to take in account that just because an exercise gets the most stimulation, doesn't mean it's the best to use. You have to take in account which ones you can use the most weight on safely to achieve mechanical muscle overload->Because IMO heavy weight builds muscle. For example, I'd achieve more overload using standing side laterals than if I did seated incline side laterals.

References:

1. DeLuca, Fj., R.S. LeFever, M.P. McCue, and A.P. Xenakis. (1982), “Behavior of human motor units in different muscles during lineally varying contractions” Journal Physiology (Lond), 329:113-128.

2. Kobayashi Matsui, H. (1983), “Analysis of myoelectric signals during dynamic and isometric contraction.” Electromyog Clin Neurophysiol, 26, 147-160.

3. Melo, G.L. and E. Cafarelli. (1994-95), Exercise Physiology Laboratory Manual, 25.

4. Moritani, T. and H.A. deVries. (1987), “Re-examination of the relationship between the surface integrated electromyogram (IEMG) and force of isometric contraction.” American Journal of Physiological Medicine, 57:263-277.

5. Moritani, T., M. Muro, and A. Nagata. (1986), “Intramuscular and surface electromyogram changes during muscle fatigue.” Journal of Applied Physiology, 60:1179-1185

[Badger]

Great stuff. You're right about the numbers, though. For instance, I absolutely love close grip benches, because it's more of a compound movement that allows me to hoist good weight to get me mentally ready for pressdowns, etc. Great info to use to help target muscle groups. I still probably won't do declines, as my lower pecs respond easily enough. Slight inclines seem to help me target the entire pec region, even though the numbers say otherwise. Thanks again for the awesome research.

[Sleazy]

Good stuff 0311.

First thing that grabbed me eye was how the exercises done with dumbbells top most of the lists number wise. Just shows how moving away from the olympic bar can benefit alot of people in the gym.

[verbatimreturned]

this may be a stupid question but why do they say olympic bar.....is there a difference between that and a standard one? (of course besides weight and thickness)

[Badger]

Probably just the easiest and most recognizable way to distinguish from the EZ bar or the bent triceps bar. Probably could have used "straight" bar, but that has alternative lifestyle connotations.

[WantingMuscle7]

That maybe should be a sticky pretty beneficial to new people and even some that have worked out for awhile.

[hrdgain81]

I just saw this now, awesome info 0311. I wonder if there are any studies on how compounds effect the minor muslce groups. for example, how effective is flat bench at stimulating tri's ect ect

[BG5150]

0311, what was the other board where you got this?

(wow, shitty grammar, but you get the idea)

If you don't wanna post it, can you PM it to me?

[Dr X]

This is good. I will have to study closer. I can see most of my favorites rise to the top.

[apocalypse]

I can see most of my favorites rise to the top.

Same here for me also, except for the declines, I dont do them all the time.