Instruction: Determine the sentiment expressed by the user in her review from the provided choices, and respond by selecting one of the available options.

Input:
I use resistance bands as part of an overall routine including a Smith Machine, free weights, pushups, and aerobics.  These are the first I've found that really can provide all the resistance one would want unless you are a true power-lifter type or professional athlete or are only interested in quads.  Even then I think you could stack them with heavier bands, but then you are really creating a different product.  With the 3 Red R4 bands it comes with, you can select one or all of them based on how many you step on.  With all 3 its pretty tough.  This is great for travel.  While its not a substitute for weight training in my opinion, it can provide a good workout to most muscle sets and certainly serves a valuable purpose when access to weights is not an option and as a supplement to weights where there are certain exercises for which I like the bands better (e.g. behind-the-back rows).  One drawback is that they are suprisingly heavy for exercise bands.  The handles are heavy plastic, which makes them sturdy, but they are heavy, and if you are not controlling the resistance well, can hurt a bit if they press against your rists or body during a movement.  On the whole, though, a great product.

Options:
A: very positive
B: positive
C: neutral
D: negative
E: very negative
Answer: A: very positive