When it comes to chin-up and pull-up training you often see two things: for one, everyone does the first rep from the bottom (because they're already at the bottom), but then they do all of their remaining reps with the assistance of A LOT of stretch reflex. They plop down and bounce out of the bottom position. 

I'll say this, if hypertrophy is your main goal with the chin-ups or pullups you're doing that day then this is probably fine(ish), assuming you don't bounce so hard that you give yourself elbow tendinitis or anything like that.

However, if your goal is to build some damn STRENGTH then this is probably not the best tactic. Similar to doing touch and go deadlifts, you are missing out on building strength in the bottom position of the movement, which often times is the weakest point of the movement. You are also creating inconsistency from rep to rep, which is not ideal when building monstrous strength is the goal.

So my work around to remedy this is simple: start every rep from the BOTTOM. Simply perform the first rep of your set as normal, and then instead of lowering down and using the eccentric to aid the following reps, you just lower down to the floor instead. Tap your feet down, regrip the bar, reset, and perform each subsequent rep in the exact same fashion as the first rep. That way every single rep in the set is exactly the same - they are ALL first reps. This way you are creating consistency from rep to rep and you are not skipping out on training the bottom of the movement. So this is going to be a very good tactic for your strength focused training sessions.

Another tactic you can do with your main chin-up or pullup work is start going a bit heavier. A big mistake that a lot of guys make is never adding substantial weight (or never adding any weight at all) to this movement, even when they are more than strong enough to merit doing so. But just like any other exercise the biggest strength gains are going to come when you start loading your chin-ups and pullups into that 3-5 rep range and performing repeat, challenging heavy sets there.

So if you can crank out 10 or more reps with body weight and you want to build a stronger chin-up, add in a session where you start loading it up and doing some heavy 3's or some heavy 5's to really start cranking your pulling strength to the next level. Chances are this work will also act symbiotically with your body weight only / higher rep work and start pushing your rep capacity to the next level as well!

Further, when you combine this heavy 3-5 rep work tactic with the dead hang strategy I mentioned initially then your chin-up strength is absolutely going to SKYROCKET. 

Pulldowns are a great assistance exercise for the chin-up because you can regress them to any resistance level. As such, they are a fantastic tool for getting in additional high quality pulling volume and cranking the hypertrophic stimulus for the lats and whatnot up to the next level. The bigger a muscle is the greater the potential it has for force production, so if your goal is to build the strongest back possible then part of that training is necessarily going to include building a bigger back as well. 

When you execute your pulldowns in a clean fashion and consistently log high quality volume they will satisfy that part of the equation as good as anything else, and that greater size will contribute to greater potential force production when you are training your heavy dead hang chin-ups concurrently!

Pulldowns are best performed in moderate or high rep ranges. In my experience, the sweet spot the majority of the time is the 10-15 rep range, as this is a moderately heavy weight that allows you to get in a good bit of challenging volume work without it being so heavy that you get sloppy. But you will also find benefit with lighter weights here as well, in the 15-20 rep range, and potentially sometimes in the 20+ range as well!

When it comes to execution, just keep it clean, man. There's really no point in doing overly sloppy pulldowns. Make sure to reach full extension at the top to get a big stretch on the lats, then pulldown explosively and squeeze those muscles hard at peak contraction.

And don't forget to vary your grips! I prefer using different widths of neutral grips for most of my pulldown training as I find that to be the most generally productive grip style with the least overall joint strain, however, you will also find value in using supinated and pronated variations from time to time as well.

Whatever chin-up grip style you're training right now, be sure to also rotate through the other styles in your upcoming sessions or training blocks as well!

When it comes to building the chin-up, we will all typically develop a favorite grip style, and that is generally going to correlate pretty strongly with whatever grip style happens to be the one we are strongest at (usually that will be a neutral grip or sometimes a supinated grip). Naturally we are going to favor that stronger style with greater volumes and greater training workloads because it's more fun to train the thing we're best at! And this is perfectly fine to an extent.

However, in the long run you just want to make sure that you don't neglect the other grip styles in favor of the one you happen to enjoy training the most. You want to make sure to give the other grip styles enough of a workload to ensure that they don't start to lag behind to a disproportionate extent.

There are 3 primary grip styles available to us for chin-ups and pull-ups: neutral grip, supinated grip, and pronated grip. Within those 3 styles you can obviously add further variation by playing with the width of each grip as well, but those are the 3 main styles available.

In my own case, for example:

1. neutral grip is my strongest: I have done a neutral grip chin-up with 160lbs of added weight

2. supinated grip is 2nd: I have done a supinated chin-up with 150lbs of added weight

3. pronated grip is 3rd: I have done a pullup with 135lbs of added weight.

So there are obvious discrepancies at play here, by my balanced workload has allowed all 3 of of the primary grip styles to flourish and grow together, preventing any major imbalances from occurring.

This has 2 positive effects for us in our chin-up journey: firstly, it creates a more well rounded pulling strength. Each of the 3 primary grip styles emphasizes or de-emphasizes different muscles enough to have a pretty large impact on the movement pattern. By being sure to train and build all 3 of them relatively equally you will create a complementary training effect where each variation helps to nudge the other variations further along (you avoid stagnation by accommodation), and there are no major weakness bottlenecks created that eventually hold back your long term progress.

Secondly, rotating through different grip styles is a solid strategy for avoiding overuse injuries. Various forms of elbow tendinopathies, for example, are major potential issues that can hold back chin-up progress when you're really pushing these movement hard. By rotating through these different grip styles accordingly we reduce the likelihood of overuse aggravation occurring in any particular facet therein, both by modulating the respective workload of each style as well as by building a more balanced and well rounded strength across all the applicable muscles. So figure out what your favorite grip style is, hit it hard for a while, and then train the opposite styles as well!