A1: If you have access to a Nordic curl apparatus, go ahead and use it for these. If not, have a partner hold your ankles and place your knees on a pad. Loop a band from above and then drape it across your chest/shoulders like a purse (NOT around your neck). Adjust the band tension as needed to fall comfortably in the rep range with perfect execution. Keep the hips extended and low back neutral throughout the entire ROM. Perform 2 sets of 15 reps on lying machine hamstring curls before the first working set here to warmup.
A2: Band around the ankles. Use a moderate strength mini band. Perform batches of 5 reps each way until you can no longer take the burn. Think about leading with your heels and keeping your hips slightly internally rotated. Hold a quarter squat position with a neutral low back.
A3: Perform these one leg at a time. Use a 4-6 inch box. Loop a moderate-tension band around the back of the knee of the working leg and anchor it ~3 feet in front of you to create a forward-pulling horizontal force vector. Slowly sink down to softly touch the heel of your non-working foot on the ground in front of the box. When you extend your knee back up, try to contract your quad hard against the band tension. Try to keep your weight in the heel if possible and allow forward knee translation over the toes. This should really bias your VMO. Tinker with these as needed to get the right feel.
B: Add a moderate-to-strong tension band from the bottom to add resistance through the concentric and lockout. The tension added from the bands should be noticeable! You may have to get creative with how you attach the bands if there are no band pegs or stable handles. Also set the stopper pins to the lowest part of the ROM that you can achieve safely. When you bring the sled down through the concentric, allow it to fully stop and settle in the pins before driving hard out of the bottom and into the concentric. Start conservative here as these get hard fast!
C1: Attach moderate strength bands from the top to reduce load in the hole! The bands should take ~25% of the total load off at the bottom. You may have to get creative with how you attach the bands if there are no band pegs or crossbars. Setup and execute these to maximize knee flexion at the bottom of the ROM to bias the quads. Adhere closely to the eccentric. Perform 2-3 feeder sets before the first working set here. Rest 60 sec before C2.
C2: Set the box height so that your thighs are parallel to the floor when seated on it. Attach chains to the bar so they add ~20% additional load when locked out at the top. The chains should deload almost completely onto the floor when seated on the box. It may take some tinkering to find the right chain weight as well as setup. Take a wider-than-normal stance during these so that you can sit into your hips more comfortably. Control the eccentric, fully settle on the box, and then perform the concentric as powerfully as possible. Full rest before returning to C1.
D1: Attach chains to the bar so they add ~25% additional load when locked out at the top. The straight weight of the bar+plates should NOT be overwhelming at the bottom of the ROM but the chains should kick in to force acceleration through the concentric. Keep these controlled on the eccentric but try to maintain a consistent touch-and-go cadence to keep the tension relatively constant. Make sure to perform feeder sets as needed before working sets here. No rest before D2.
D2: Start in a quadruped position with your feet right under a box and a light tension band looped under your hands and around the backs of the knees. Then elevate feet on a 12-18in box. As you extend at the knees, the band will kick in harder and resist the extension forcing the quads to work harder. This should resemble a leg extension pattern from the perspective of the quads but will be a full body workout to provide the stability needed to sustain the effort. Think about burning out the quads here! Full rest before returning to D1.
As strength training enthusiasts, we have a seemingly infinite amount of modalities at our disposal.
Barbells and dumbbells have been the standard for decades, but now we have an overwhelming assortment of options to choose from when trying to find the right medium for our torture.
Kettlebells have become an international sensation for their versatility and unique application. Cable systems and machines are nothing new, but consistent innovation in the field/understanding of biomechanics has led to a new wave of engineering mastery. Then we have the more niche spectrum of use cases that can be addressed with stuff like suspension straps, sandbags, maces, kegs, specialty bars, Fat-bells, medicine balls, and on and on and on.
If you have a problem that needs fixin', there is guaranteed to be a modality that can provide that solution.
All of the listed equipment above is what I would consider primary modalities; they are the source of the external load or resistance.
But there is another supplementary class of equipment that have the potential to create just as much, if not more, stimulus and positive change when integrated correctly.
These secondary modalities act complementarily to provide accommodating resistance, enable alternative force vectors, or even allow for purposeful changes in stability that are independent of the primary method of loading.
Resistance bands and chains are the most common (and generally, most effective) tools that slot into this role.
But why would we even care about these secondary modalities? Is one source of resistance not enough?
"Good enough" is the enemy of optimal. And while chasing optimality is a perpetually futile pursuit, we shouldn't use this as an excuse to dismiss potential improvements to the way we train. If there are specific variations or techniques or modalities that distance us from mediocrity, we would be downright stupid to disregard their efficacy—it's at least worth a shot!
The key to effectively layering on a secondary modality is going to be through respecting hierarchies...Adding band tension to a leg press is a potent tool but not at the expense of overshadowing the "real" load. Similarly, implementing chains to your bench press routine can do wonders for increasing power and lockout strength, but if those chains are set-up incorrectly and force you out of your groove, you can kiss any potential benefits goodbye. The moment the secondary begins to compromise the primary is when the plot has been lost. Don't lose the plot.
And just because you can use a modality doesn't mean you should...
Many of the implementations of bands and chains are going to be best taken advantage of once a solid foundation has been laid. Mastering and building on top of primary modalities will be where 90% of your lifetime gains come from. It's important to not overlook that fact just because something shiny and new and cool has been introduced.
Beginners should spend 100% of their time working on proper technique, body control and neuromuscular coordination. Intermediates should then spend nearly 100% of their time transferring what was learned as a beginner into productive action with the primary modalities. If/when intermediates graduate into an advanced trainee, the goals then shift towards individuality with specific needs being addressed through variation and, sometimes, novelty.
And note that it is only at this last stage of the cycle that new things need to be introduced in order to propagate further progress and circumvent stagnation. Most trainees will be able to make relatively linear progress for years by exclusively focusing on perfecting execution on their primaries and learning to train with intensity.
Now that I'm done waxing poetic about the nuances of using bands and chains as supplements to your training, it should be much easier to look at the program written here and clearly see the connections to what I'm saying. All of the exercises and techniques have a clear order of operations—the primary pattern/modality/stimulus is meant to be improved by the addition of the bands or chains. The secondaries don't force change onto the primaries; instead, they take "good enough" and make it better.