When people ask me how to build big triceps I respond with two simple words; "do dips." Do dips and do a lot of them. Why, you ask? Have you seen the triceps development on male gymnasts lately? The dip is basically the only true triceps move they do and they are absolutely jacked with huge, thick, horseshoe triceps. Whenever you use your bodyweight for resistance or bodyweight plus additional resistance via a chin/dip belt or weight vest, you activate a much greater number of muscle fibers than you would if you simply used a machine. Machines do not recruit the smaller stabilizer muscles and do not force the muscles to contract naturally as they would in real life. Whenever possible you want to try to move your body instead of simply moving the arm or attachment on a machine. And although free weight exercises are very effective and a much better option than training on a machine, moving your own bod will always reign supreme when it comes to building muscle.
Dips can be performed on parallel bars or, if you are really strong, gymnastics rings. Be sure to squeeze the bars tightly, brace your abs as if you were about to be punched and lower yourself no lower than the point where your triceps are parallel with the ground. Going lower than that puts too much stress on the shoulders and getting the extra stretch is not worth the risk of an injury.
Dips can be performed three times per week as a beginner. After a few months of that I don't think you will be confused about how to build big triceps anymore. When you get more advanced it is recommended to cut your dips down to twice per week. Although I used to love weighted dips and routinely had many of my clients perform them with numerous 45 pound plates strapped to their waists I have found, over the years, that there is simply too great a risk of injury with heavy weighted dips and now do not allow anyone in my gym to do dips with more than just one 45 pound plate. Anything beyond that seems to get too risky.
For intermediate lifters you could do one day heavy, where you add resistance to your weight belt, and one day light where you simply rep out with bodyweight. The two days should be about 72 hours apart. Once you get strong enough to do a 45 pound plate you will probably only want to use weighted dips as a rep exercise and not a heavy strength movement anymore.
To make dips more difficult without adding more weight, try doing them on gymnastics rings or on straps. You can also try holding your legs straight out directly in front of you as well. Either option will be very challenging and are great muscle builders.
Aside from dips, the next best muscle building exercise for the triceps is a reduced range of motion close grip bench press or some variation of it. The top half of the bench press really focuses the stress on the triceps which is why you want to limit the range when training simply to increase the size of your arms. To do this you can set pins in a power rack or have a partner hold a few two by fours on your chest. These are called board presses. Three, four and five boar presses are awesome for building huge triceps and should be incorporated into your routine on a regular basis. When you get too strong to go heavy on dips without risking a shoulder injury, make board presses your heavy triceps movement and dips your light triceps movement. Keep pushing up the weight and reps and pretty soon people will be asking you about how to build big triceps like yours.
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