gistfile1.m

NSURL *url = [NSURL URLWithString:@"https://mysite.com/"];
AFHTTPClient *httpClient = [[AFHTTPClient alloc] initWithBaseURL:url];

NSDictionary *params = [NSDictionary dictionaryWithObjectsAndKeys:
                        height, @"user[height]",
                        weight, @"user[weight]",
                        nil];
NSMutableURLRequest *request = [httpClient requestWithMethod:@"POST" path:@"/myobject" parameters:params];

AFHTTPRequestOperation *operation = [AFHTTPRequestOperation operationWithRequest:request
                                     completion:^(NSURLRequest *req, NSHTTPURLResponse *response, NSData *data, NSError *error) {
    BOOL HTTPStatusCodeIsAcceptable = [[NSIndexSet indexSetWithIndexesInRange:NSMakeRange(200, 100)] containsIndex:[response statusCode]];
    if (HTTPStatusCodeIsAcceptable) {
        NSLog(@"Request Successful");
    } else {
        NSLog(@"[Error]: (%@ %@) %@", [request HTTPMethod], [[request URL] relativePath], error);
    }
}];

NSOperationQueue *queue = [[[NSOperationQueue alloc] init] autorelease];
[queue addOperation:operation];